Carbon-fluorine bond activation by organic photoredox catalyst and processes for converting organofluorides

Abstract

Embodiments described herein generally relate to processes for activation of C‒F bonds using an organic photoredox catalyst. Embodiments described herein also relate to processes for converting a substrate comprising a C‒F bond to a conversion product. In an embodiment, a process for converting an organofluoride is provided. The process includes forming a reaction mixture comprising an organofluoride, an organic catalyst, a co-catalyst, and a hydrogen source. The process further includes exposing the reaction mixture to light to convert the organofluoride to a conversion product. In another embodiment, a process for converting an organofluoride is provided. The process includes forming a reaction mixture comprising an organofluoride, an organic catalyst, a co-catalyst, and a coupling partner. The process further includes exposing the reaction mixture to light to convert the organofluoride to a conversion product.

Description

CARBON-FLUORINE BOND ACTIVATION BY ORGANIC PHOTOREDOXCATALYST AND PROCESSES FOR CONVERTING ORGANOFLUORIDESGOVERNMENT SUPPORT

[0001] This invention was made with government support under grant no. 2016557 awarded by the National Science Foundation and grant no. R35 GM144356 awarded by the National Institutes of Health. The government has certain rights in the invention.FIELD

[0002] Embodiments described herein generally relate to processes for activation of carbon-fluorine (C-F) bonds using an organic photoredox catalyst and to processes for converting a substrate comprising a C-F bond to a conversion product.BACKGROUND

[0003] Photoredox catalyzed activation of organohalides has offered a broadly applicable strategy in chemical synthesis because the halide serves as a versatile functional group for elimination, substitution, and cross-coupling reactions. However, conventional technologies for activation of carbon-halogen bonds have rarely extended to organofluorides which are the most commercially abundant organohalide. Conventional approaches based on photoredox chemistry for activation of C-F bonds are limited by, for example, the requirement of transition-metal catalysts or main group Lewis-acid catalysts as well as the limited scope of organofluoride substrates. Here, conventional transition-metal catalysts are tailored to individual substrates, indicating the lack of catalysts for broad-spectrum use. When transitional-metal catalysts are not utilized, very high temperatures are required that decompose the C-F substrates. Therefore, developing a general method for the direct activation of organofluorides would have major implications for organic synthesis.

[0004] Recently, perfluoroalkyl and polyfluoroalkyl substances (PF AS compounds) have attracted significant attention. Because of their widespread use and their persistence in the environment, these forever chemicals present potential human health and environmental risks. However, no general strategy has emerged for direct C-F bond activation of alkyl and aryl fluorides, PF AS, or fluorinated polymers.

[0005] There is a need for new processes for the activation of C-F bonds using an organic photoredox catalyst. There is also a need for processes for converting substrates comprising a C-F bond to a conversion product.SUMMARY

[0006] Embodiments of the present disclosure generally relate to processes for the activation of C-F bonds using an organic photoredox catalyst and to processes for converting a substrate comprising a C-F bond to a conversion product. Methodologies and processes described herein enable efficient reduction of C-F bonds to generate carbon-centered radicals that may be utilized for hydrodefluorination reactions and cross-coupling reactions. Methodologies and processes described herein enable the general use of organofluorides as substrates (starting materials) under mild reaction conditions. Moreover, the methodologies and processes described herein may be utilized for defluorination of PFAS compounds and fluorinated polymers. Unlike conventional technologies for photoredox catalyzed C-F bond activation, embodiments described herein overcome the constraints of specific substrates and the requirement of transition-metal catalysts or main group Lewis-acid catalysts. Further, embodiments described herein may be used at temperatures significantly below those of conventional technologies.

[0007] In an embodiment, a process for converting an organofluoride to a conversion product is provided. The process may include forming a reaction mixture comprising an organofluoride, an organic catalyst, a co-catalyst, a hydrogen source, and an optional solvent, the organofluoride represented by formula (I):R1F k (I), wherein: each of R1and R2of formula (I) are, independently, hydrogen, unsubstituted hydrocarbyl, substituted hydrocarbyl, or a functional group comprising at least one element from Group 13-17 of the periodic table of the elements; and at least one of R1or R2of formula (I) is the unsubstituted hydrocarbyl, the substituted hydrocarbyl, or the functional group comprising at least one element from Group 13-17. The process may further include exposing the reaction mixture to light to convert the organofluoride, under conversion conditions, to a conversion product represented by formula (II):

[0008] Implementations may include one or more of the following. The organic catalyst may be metal free. The organic catalyst may include a benzo[ghi]perylenemoiety represented by formula (VII) and / or a benzo[ghi]perylene moiety represented by formula (VII- A):wherein the wavy bonds of formula (VII-A) represent connections to an unsubstituted hydrocarbyl, a substituted hydrocarbyl, or a functional group comprising at least one element from Group 13-17. The co-catalyst may include nBu4NF, Et4Nf, Me4NF,Me4N0H, or combinations thereof; the hydrogen source may include an alcohol; the optional solvent may include tetrahydrofuran, dimethylformamide, dichloromethane, toluene, dimethylacetamide, acetonitrile, dimethyl sulfoxide, or combinations thereof; or combinations thereof. At least one of R1or R2of formula (I) may be an unsubstituted hydrocarbyl having 1 to 20 carbon atoms or a substituted hydrocarbyl having 1 to 20 carbon atoms. The conversion conditions may include a temperature that is about 100°C or less. The light may have a wavelength that is from about 300 nm to about 800 nm, or from about 350 nm to about 450 nm.

[0009] In another embodiment, a process for converting a PFAS compound to a conversion product is provided. The process includes forming a reaction mixture comprising a PFAS compound, a metal-free organic catalyst, a co-catalyst, a hydrogen source, and an optional solvent, the PFAS compound represented by formula (III):wherein: each of R3and R4of formula (III) are, independently, hydrogen, unsubstituted hydrocarbyl, substituted hydrocarbyl, or a functional group comprising at least one element from Group 13-17 of the periodic table of the elements; and at least one of R3or R4of formula (III) is the unsubstituted hydrocarbyl, the substituted hydrocarbyl, or the functional group comprising at least one element from Group 13-17. The process further includes exposing the reaction mixture to light to convert the PFAS compound to a conversion product represented by formula (IV):

[0010] Implementations may include one or more of the following. At least one of R3or R4of formula (III) may be an unsubstituted hydrocarbyl having 1 to 20 carbon atoms or a substituted hydrocarbyl having 1 to 20 carbon atoms. At least one of R3or R4of formula (III) may be a substituted hydrocarbyl comprising 1 to 20 carbons and a hydroxyl (-OH) group. At least one of R3or R4of formula (III) may be a substituted hydrocarbyl comprising 1 to 3 carbons and a hydroxyl (-OH) group. At least one of R3or R4of formula (III) may include an ester represented by formula (V-A):wherein: R5of formula (V-A) is an unsubstituted hydrocarbyl comprising 1 to 6 carbon atoms; the wavy bond of formula (V-A) represents a connection to the -CF2- group of the PFAS compound of formula (III); and the wavy bond 1 ^ ) of formula (V-A) represents a connection to the methylene (-CH2-) group of the conversion product of formula (IV). At least one of R3or R4of formula (III) may include a substituted aryl or an unsubstituted aryl. At least one of R3or R4of formula (III) may include a carboxylic acid represented by formula (V-B):wherein the wavy bond 1 ^ ) of formula (V-B) represents a connection to the -CF2- group of the PF AS compound of formula (III). When at least one of R3or R4of formula (III) includes a carboxylic acid represented by formula (V-B) described herein, the carboxylic acid may be converted to an ester by the process.

[0011] In another embodiment, a process for converting an organofluoride to a conversion product is provided. The process includes forming a reaction mixture comprising an organofluoride, a metal-free organic catalyst, a co-catalyst, a coupling partner comprising at least one element from Group 13-16 of the periodic table of the elements, and an optional solvent, the organofluoride represented by formula (I):R1.FR2(I),wherein: each of R1and R2of formula (I) are, independently, hydrogen, unsubstituted hydrocarbyl, substituted hydrocarbyl, or a functional group comprising at least one element from Group 13-17; and at least one of R1or R2of formula (I) is the unsubstituted hydrocarbyl, the substituted hydrocarbyl, or the functional group comprising at least one element from Group 13-17. The process further includes exposing the reaction mixture to light to convert the organofluoride to a conversion product represented by formula (VI):wherein A" of formula (VI) comprises the at least one element from Group 13-16.

[0012] Implementations may include one or more of the following. The conversion product of formula (VI) may be represented by formula (VI-A), formula (VI-B), or formula (VI-C):The conversion product of formula (VI) may be represented by formula (VI-D):The conversion product of formula (VI) may be represented by formula (VI-E):wherein Z" of formula (VI-E) is aryl, optionally substituted by one or more substituents comprising an unsubstituted hydrocarbyl, a substituted hydrocarbyl, or a functional group comprising at least one element from Groups 13-17; or Z" of formula (VI-E) is heteroaryl, optionally substituted by one or more substituents comprising an unsubstituted hydrocarbyl, a substituted hydrocarbyl, or a functional group comprising at least one element from Groups 13-17. The conversion product of formula (VI) may be represented by formula (VI-F):wherein X of formula (VI-F) is S or Se; and RAof formula (VI-F) is an unsubstituted hydrocarb yl or a substituted hydrocarbyl.BRIEF DESCRIPTION OF THE DRAWINGS

[0013] So that the manner in which the above recited features of the present disclosure may be understood, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. The appended drawings illustrate only exemplary embodiments and are not to be considered limiting of its scope, and the exemplary embodiments may admit to other equally effective embodiments.

[0014] FIGS. 1A and IB show a general overview of an organic photocatalytic system, which includes an organic catalyst (BPI), for activating C-F bonds for hydrodefluorination and cross-coupling reactions according to at least one embodiment of the present disclosure.

[0015] FIG. 2 shows a proposed mechanism for a photoredox-catalyzed dehalogenation of fluorobenzene according to at least one embodiment of the present disclosure.

[0016] Figures included herein illustrate various embodiments of the disclosure. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.DETAILED DESCRIPTION

[0017] Embodiments of the present disclosure generally relate to processes for activation of C-F bonds using an organic photoredox catalyst and to processes for converting a substrate comprising a C-F bond (an organofluoride) to a conversion product.

[0018] Organofluorides have a large impact in medicinal, agrochemical, and materials sciences as fluorine incorporation results in structures imparting specific beneficial attributes and is used to tune properties derived from secondary interactions with the molecular environment. Many pharmaceuticals and agrochemicals contain fluorine because of the favorable interactions derived from hydrogen bonding at protein active sites. Substitution of hydrogen in the structure of the commodity plastic polyethylene with fluorine leads to high-performance polytetrafluoroethylene (Teflon) with superior thermal, mechanical, and stability properties, inspiring continued development of fluorine-containing polymers for use in high-end applications. Due to opportunities imparted by fluorine incorporation, significant efforts have been made todevelop synthetic methods for the synthesis of fluorine-containing compounds. From an alternative perspective, the prevalence of fluorinated organic molecules makes the C-F bond an attractive functional group for further chemical modification. However, properties such as strong C-F bond strength, hydrophobicity, and high thermal stability that bestow unique properties into fluorinated compounds also equate to chemical inertness. Consequently, not only are C-F bonds challenging to activate but their stability results in environmental persistence. Serious concerns regarding environmental contamination by fluorinated molecules exist because they are pervasive in the environment and long-term exposure may result in adverse health effects.

[0019] Conventional approaches to C-F bond activation rely on transition metal or main group Lewis-acid catalysts and are challenged by scope limitations and issues of substrate generality. Recently, the advent of low-energy, visible-light photoredox catalysis has offered a broadly applicable carbon-halogen (halogen: Cl, Br, or I) bond activation strategy, which has led to an increase in the use of radical chemistry to tackle such synthetic problems. However, no general strategy has yet emerged for direct C-F bond activation of organofluorides (e.g., alkyl and aryl fluorides, per- and polyfluoroalkyl substances (PFAS), or fluorinated polymers). To date, conventional photoredox catalyzed C-F bond activation has centered on nucleophilic aromatic substitution by an oxidative reaction mechanism, are limited to specific substrates (polyfluorinated arenes, trifluoromethyls, or fluoroamides), require stoichiometric reagents, use high energy UV light, rely on an anionic bimetallic complex, and / or are limited to only a few catalyst turnovers. A fundamental challenge in photoredox- catalyzed C-F bond activation is that the reducing strength of conventional photoredox catalysts is insufficient to engage this inert bond. To accommodate a diverse range of chemical complexities and C-F bond strengths, this activation step would require a photoredox catalyst system with a strong electron transfer capability not found in the state-of-the-art.

[0020] The inventors have discovered processes that overcome such challenges. FIGS. 1A and IB show a general overview of an organic photocatalytic system for activating challenging C-F bonds for hydrodefluorination and cross-coupling reactions. In various embodiments, fluorine-containing starting materials (organofluorides 101) such as aryl fluorides, alkyl fluorides, PFAS compounds, and fluorinated polymers, may be converted to reduction products 102 using an organic catalyst (a benzo-perylene monoimide (BPI), FIG. IB), an electron donor or electrode,and a hydrogen source under light irradiation such as visible light. Hydrogen sources (also referred to as proton sources) for the conversion of organofluorides 101 to reduction products 102 may include any suitable alcohol or other material. In various alternative embodiments, organofluorides 101 may be converted to cross-coupling products 103 using an organic catalyst, an electron donor, and a coupling partner A1(or reactant) under light irradiation such as visible light. Cross-coupling products 103 may include a functional group A2comprising at least one element from Group 13-16 of the periodic table of the elements. Such a cross-coupling reaction to cross-coupling products 103 may include borylation, phosphonylation, arylation, heteroaryl ati on, sulfuration, and selenization reactions, among others. The catalyst may include BPI. The co-catalyst, which may serve as a sacrificial electron donor, may include a quaternary ammonium such as tetra-w-butylammonium fluoride or tetramethylammonium hydroxide, among others. The combination of the BPI catalyst and the co-catalyst (also referred to as an electron donor) under light irradiation provides a photocatalytic system that activates a C-F bond of various fluorine- containing starting materials. Following an electron transfer (ET) event, the C-F bond is cleaved to generate carbon-centered radicals that may be used for either hydrodefluorination to form reduction products 102 or cross-coupling reactions to form cross-coupling products 103.

[0021] Embodiments described herein relate to processes for converting a substrate comprising a C-F bond, such as organofluoride 101, to a conversion product. Processes described herein include conversion of an organofluoride to a conversion product such as reduction product 102. Processes described herein also include conversion of a PF AS compound to a conversion product such as reduction product 102. Processes described herein also include conversion of a fluorinated polymer to a conversion product such as reduction product 102. Processes described herein also include conversion of an organofluoride to cross-coupling products, where the cross-coupling products 103 may include a newly formed carbon-boron (C-B) bond, carbon-phosphorous (C-P) bond, carbon-carbon (C-C) bond, carbon-sulfur (C-S) bond, or carbon-selenium (C-Se) bond.

[0022] The use of headings is for purposes of convenience only and does not limit the scope of the present disclosure. Embodiments described herein can be combined with other embodiments. For example, features and elements of one describedembodiment may be combined with other embodiments within the scope of the present disclosure.Conversion of Organofluorides to Conversion Products

[0023] In an embodiment, which may be combined with other embodiments, a process for converting an organofluoride to a conversion product is provided. The process may include: (a) forming a reaction mixture comprising an organofluoride, an organic catalyst, a co-catalyst, a hydrogen source, and an optional solvent; and (b) exposing the reaction mixture to light to convert the organofluoride, under conversion conditions, to a conversion product. This process is a reduction reaction (a hydrodefluorination) to form a conversion product, e.g., reduction product 102.

[0024] The organofluoride is utilized as the substrate comprising a C-F bond, or the starting material, for the conversion. The organofluoride may be an alkyl fluoride or an aryl fluoride, among other organofluorides. The organofluoride may include one or more fluorine atoms. For example, the organofluoride may include fluorine atoms covalently bonded to the same carbon atom. Additionally, or alternatively, the organofluoride may include fluorine atoms covalently bonded to different carbon atoms. The organofluoride may be represented by formula (I):wherein: each of R1and R2of formula (I) are, independently, hydrogen, unsubstituted hydrocarbyl, substituted hydrocarbyl, or a functional group comprising at least one element from Group 13-17 of the periodic table of the elements; and at least one of R1or R2of formula (I) is the unsubstituted hydrocarbyl, substituted hydrocarbyl, or functional group comprising at least one element from Group 13-17 of the periodic table of the elements.

[0025] R1and R2of formula (I) may be the same or different. One or more of R1and R2of formula (I) may be, independently, linear or branched, saturated or unsaturated, cyclic or acyclic, monocyclic or polycyclic, aromatic or not aromatic. Regarding saturation, one or more of R1and R2of formula (I) may be, independently, fully saturated, partially unsaturated, or fully unsaturated. Two or more R groups (e.g., R1and R2, or other R groups within the same molecule described herein) may join together to form a substituted or unsubstituted, completely saturated, partially unsaturated, fully unsaturated, or cyclic, aromatic cyclic, or polycyclic ring structure.As an illustrative, but non-limiting, example, R1and R2may join to form an aromatic ring, such as phenyl, such that formula (I) is fluorobenzene.

[0026] As used herein, an “un substituted hydrocarbyl” refers to a group that consists of hydrogen and carbon atoms only. Non-limiting examples of unsubstituted hydrocarbyl include an alkyl group having from 1 to 100 carbon atoms, such as from 1 to 20 carbon atoms, such as 3 to 10 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, sec-butyl, and tert-butyl, pentyl, hexyl, heptyl, octyl, ethyl -2 -hexyl, isooctyl, nonyl, n-decyl, isodecyl, or isomers thereof; a cycloaliphatic group having from 3 to 20 carbon atoms such as, for example, cyclopentyl or cyclohexyl; an aromatic group having from 6 to 20 carbon atoms such as, for example, phenyl or naphthyl; or any combination thereof.

[0027] As used herein, “substituted hydrocarbyl” refers to an unsubstituted hydrocarbyl in which at least one hydrogen of the unsubstituted hydrocarbyl has been substituted with at least one heteroatom or heteroatom-containing group, such as one or more elements from Group 13-17 of the periodic table of the elements, such as halogen (F, Cl, Br, or I), O, N, Se, Te, P, As, Sb, S, B, Si, Ge, Sn, Pb, and the like, such as C(O)R*, C(C)NR*2, C(O)OR*, NR*2, OR*, SeR*, TeR*, PR*2, AsR*2, SbR*2, SR*, SOX(where x = 2 or 3), BR*2, SiR*3, GeR*3, SnR*3, PbR*3, and the like, where R* is, independently, hydrogen or unsubstituted hydrocarbyl, or where at least one heteroatom has been inserted within the unsubstituted hydrocarbyl.

[0028] When an R group (e.g., R1and / or R2, or other R group described herein) is a functional group comprising at least one element from Group 13-17 of the periodic table of the elements, the R group may be halogen (F, Cl, Br, or I), O, N, Se, Te, P, As, Sb, S, B, Si, Ge, Sn, Pb, and the like, such as C(O)R*, C(C)NR*2, C(O)OR* (e.g., ester), NR*2, OR*, SeR*, TeR*, PR*2, AsR*2, SbR*2, SR*, SOX(where x = 2 or 3), BR*2, SiR*3, GeR*3, SnR*3, PbR*3, and the like, where R* is, independently, hydrogen or unsubstituted hydrocarbyl, or where at least one heteroatom has been inserted within the unsubstituted hydrocarbyl.

[0029] As used herein, “aryl” and “aryl group” interchangeably refer to a hydrocarbon ring system comprising hydrogen, 5 to 30 carbon atoms (such as 6 to 14 carbon atoms), and at least one aromatic ring. The aryl or aryl group may be a monocyclic, bicyclic, or tricyclic system and which may include spiro ring systems. The aryl may be unsubstituted or substituted by one or more substituents comprising an unsubstituted hydrocarbyl, a substituted hydrocarbyl, or a functional group comprisingat least one element from Group 13-17 of the periodic table of the elements, such as halogen (F, Cl, Br, or I), O, N, Se, Te, P, As, Sb, S, B, Si, Ge, Sn, Pb, and the like, such as NR*2, OR* (e.g., OH or O2H), SeR*, TeR*, PR*2, AsR*2, SbR*2, SR*, SOX(where x = 2 or 3), BR*2, SiR*3, GeR*3, SnR*3, PbR*3, and the like or where at least one heteroatom has been inserted within the hydrocarbyl radical or aryl radical such as one or more of halogen (Cl, Br, I, F), O, N, S, Se, Te, NR*, PR*, AsR*, SbR*, BR*, SiR*2, GeR*2, SnR*2, PbR*2, and the like, where R* is, independently, hydrogen, or hydrocarbyl (e.g., Ci-Cio), or two or more R* may join together to form a substituted or unsubstituted completely saturated, partially unsaturated, fully unsaturated, or cyclic, aromatic cyclic, or polycyclic ring structure. When the aryl is unsubstituted, the aryl may be referred to as an unsubstituted aryl. When the aryl is substituted, the aryl may be referred to as a substituted aryl.

[0030] As used herein, “heteroaryl” and “heteroaryl group” interchangeably refer to a 5- to 30-membered ring system comprising hydrogen atoms, one to 29 carbon atoms, one or more heteroatoms, and at least one aromatic ring. For example, a heteroaryl group may include a 5- to 14-membered ring system comprising hydrogen atoms, one to thirteen carbon atoms, one to six heteroatoms, and at least one aromatic ring. Heteroatoms of the heteroaryl group may include nitrogen, oxygen, sulfur, or combinations thereof. Illustrative, but non-limiting, examples may include pyrrolidinyl, pyridinyl, furanyl, thiophenyl, imidazolidinyl, or oxazolidinyl, among others. The heteroaryl may be unsubstituted or substituted by one or more substituents comprising an unsubstituted hydrocarbyl, a substituted hydrocarbyl, or a functional group comprising at least one element from Group 13-17 of the periodic table of the elements, such as halogen (F, Cl, Br, or I), O, N, Se, Te, P, As, Sb, S, B, Si, Ge, Sn, Pb, and the like, such as NR*2, OR* (e.g, OH or O2H), SeR*, TeR*, PR*2, AsR*2, SbR*2, SR*, SOX(where x = 2 or 3), BR*2, SiR*3, GeR*3, SnR*3, PbR*3, and the like or where at least one heteroatom has been inserted within the hydrocarbyl radical or aryl radical such as one or more of halogen (Cl, Br, I, F), O, N, S, Se, Te, NR*, PR*, AsR*, SbR*, BR*, SiR*2, GeR*2, SnR*2, PbR*2, and the like, where R* is, independently, hydrogen, or hydrocarbyl (e.g., Ci-Cio), or two or more R* may join together to form a substituted or unsubstituted completely saturated, partially unsaturated, fully unsaturated, or cyclic, aromatic cyclic, or polycyclic ring structure. When the heteroaryl is unsubstituted, the heteroaryl may be referred to as an unsubstituted heteroaryl. When the heteroaryl is substituted, the heteroaryl may be referred to as a substituted heteroaryl.

[0031] The organofluoride of formula (I) may have two or more fluorine atoms. One or more of these fluorine atoms may be part of an R group. The fluorine atoms on an R group may optionally react under processes described herein.

[0032] The conversion product formed in operation (b) of the conversion of the organofluoride may be represented by formula (II):R1HR2(II), wherein: each of R1and R2in formula (II) is, independently, hydrogen, unsubstituted hydrocarbyl, a substituted hydrocarbyl, or a functional group comprising at least one element from Group 13-17 of the periodic table of the elements, such as an R group described herein for R1or R2.

[0033] The organic catalyst may be metal free. The organic catalyst may include a benzo[ghi]perylene moiety represented by formula (VII):

[0034] The benzo[ghi]perylene moiety represented by formula (VII) may be represented by formula (VII- A):wherein the wavy bonds of formula (VII-A) represent connections to an unsubstituted hydrocarbyl, a substituted hydrocarbyl, or a functional group comprising at least one element from Group 13-17 of the periodic table of the elements. An illustrative, but non-limiting, example of the organic catalyst that includes a benzo[ghi]perylene moiety may include 2-(2-ethylhexyl)-6,8,l l-tris(4-methoxyphenyl)-lH-peryleno[l,12- efg]isoindole-l,3(2H)-dione (also referred to herein as BPI). BPI has the structure represented by formula (VII-B):

[0035] Any suitable co-catalyst may be utilized for the conversion of the organofluoride to the conversion product. The co-catalyst serves as a sacrificial electron donor for the conversion. The co-catalyst may include quaternary ammoniums, hydroxides, or combinations thereof, such as tetra-n-butylammonium fluoride (also known as nBu4NF or TBAF), tetra-methylammonium hydroxide (Me4N0H), tetraethylammonium fluoride (EXjNF), tetra-methylammonium fluoride (Me4NF), tetra-n- butylammonium chloride (nBu4NCl), tetra-n-butylammonium bromide (nBu4NBr), or combinations thereof, such as nBu4NF, Me4N0H, or combinations thereof.

[0036] The co-catalyst may be added to the reaction mixture as a co-catalyst solution. For example, a nBu4NF solution that includes the nBu4NF and a solvent may be used. Any suitable concentration of the co-catalyst solution may be utilized. For example, a 0.1M to 10M solution of co-catalyst in solvent, such as a 0.5M to 5M, such as 0.8M to 1.2M, such as about IM may be utilized. The solvent for the co-catalyst solution may include THF. The solvent for the co-catalyst solution may be different than the optional solvent utilized for the reaction mixture. For example, the co-catalyst solution may include THF and the optional solvent may include MeOH.

[0037] Additionally, or alternatively, the co-catalyst may include an electrode. Here, the electrode serves as a source of electrons. When utilized, an anode and a cathode may be immersed in the reaction mixture and an electric field is applied to the reaction mixture by use of the anode and the cathode to promote or cause a reaction to occur. Other set-ups for the electrode are contemplated. The electric field applied may have a voltage that is from about -2 V to about -3 vs ferrocene / ferrocenium (Fc / Fc+).

[0038] Any suitable hydrogen source may be utilized for the conversion of the organofluoride to the conversion product. The hydrogen source may include dimethylformamide (DMF), any suitable alcohol, or combinations thereof. Suitablealcohols as hydrogen sources may include, but are not limited to, tert-amyl alcohol (also referred to as tert-AmylOH, t-AmylOH, or 2-methylbutan-2-ol), methanol (MeOH), ethanol (EtOH), isopropyl alcohol (iPrOH), glycerol, benzyl alcohol, or combinations thereof, such as tert-AmylOH, MeOH, EtOH, iPrOH, or combinations thereof, such as tert-AmylOH, MeOH, or combinations thereof.

[0039] Any suitable optional solvent may be utilized for the conversion of the organofluoride to the conversion product. The optional solvent may include tetrahydrofuran (THF), DMF, dichloromethane (DCM), toluene, dimethylacetamide (DMac), acetonitrile (MeCN), dimethyl sulfoxide (DMSO), acetone, pyridine, toluene, or combinations thereof, such as THF, DMF, DCM, toluene, MeCN, DMSO, MeOH, or combinations thereof, such as THF, MeCN, DMSO, MeOH, or combinations thereof. The optional solvent may include a mixture of two or more solvents in suitable proportions. For example, the optional solvent may include THF and MeCN. Alternatively, the optional solvent may include THF and DMSO.

[0040] The process for converting the organofluoride to the conversion product of formula (II) may be performed under any suitable conversion conditions sufficient to form the conversion product.

[0041] Conversion conditions at operation (b) of the process to convert the organofluoride may include any suitable conversion temperatures. Suitable conversion temperatures may include room temperature (from about 20°C to about 25°C), elevated temperatures (temperatures above room temperature), or combinations thereof. Suitable conversion temperatures may be about 100°C or less, about 50°C or less, about 40°C or less, about 30°C or less. Suitable temperatures may be from about -10°C to about 100°C, such as from about 0°C to about 80°C, such as from about 5°C to about 70°C, such as from about 10°C to about 60°C, such as from about 20°C to about 50°C. Additionally, or alternatively, the conversion temperature may be greater than the freezing point of the solvent, less than the boiling point of the solvent, or combinations thereof. The conversion temperature is the temperature monitored by a temperature probe.

[0042] Conversion conditions at operation (b) of the process to convert the organofluoride include may include any suitable conversion pressure. The conversion pressure may be about 5 atm or less, such as from about 0.8 atm to about 1.2 atm, such as from about 0.9 atm to about 1.1 atm, such as about 1 atm.

[0043] The conversion may be performed for any suitable conversion period. The conversion period may be about 200 hours or less, such as about 100 hours or less, such as about 80 hours or less, such as about 50 hours or less, such as about 24 hours or less, such as about 20 hours or less, such as from about 1 hour to about 100 hours, such as from about 5 hours to about 80 hours, such as from about 10 hours to about 60 hours, such as from about 16 hours to about 48 hours. The conversion period is based on the length of exposure of the reaction mixture to the light.

[0044] The components of the reaction mixture at operation (b) of the process to convert the organofluoride may be mixed, stirred, or agitated by using suitable devices such as a mechanical stirrer, such as an overhead stirrer, a magnetic stirrer (for example, placing a magnetic stir bar in the vessel above a magnetic stirrer), a batch reaction vessel, a semi-batch reaction vessel, a continuous static mixer, or other suitable devices. For example, a stirrer having a blade or propeller may be rotated by receiving rotational power from a stirring motor to stir the one or more materials at suitable rotation speeds. Suitable rotation speeds may include from about 50 revolutions per minute (rpm) to about 1,500 rpm, such as from about 75 rpm to about 1,000 rpm, such as from about 100 rpm to about 900 rpm, such as from about 200 rpm to about 800 rpm, such as from about 300 rpm to about 700 rpm, such as from about 400 rpm to about 600 rpm, such as from about 450 rpm to about 550 rpm, such as about 500 rpm. Other rotation speeds are contemplated and may be selected based on the ability to mix the components sufficiently. Mechanical agitation or jet mixing may be used. Components of the reaction mixture at operation (b) may be mixed, stirred, or agitated in the presence of a non-reactive gas, such as nitrogen (N2), argon (Ar), or combinations thereof. For example, a non-reactive gas may be introduced with one or components in the reaction mixture to degas various components or otherwise remove unwanted gases such as oxygen from the reaction mixture.

[0045] Suitable molar ratios of the organic catalyst to the organofluoride in the reaction mixture may be from about 1 :20 to about 1 :2,000, such as from about 1 :40 to about 1 : 1,000, such as from about 1 :75 to about 1 :500, such as from about 1 : 100 to about 1 :300, such as from about 1 : 150 to about 1 :250, such as about 1 :200. For example, the reaction mixture may include about 2.5 pmol of the organic catalyst and about 0.5 mmol of the organofluoride.

[0046] Suitable molar ratios of the organofluoride to the co-catalyst in the reaction mixture may be from about 1 :0.1 to about 1 :30, such as from about 1 :0.5 to about 1 : 18,such as from about 1 :0.8 to about 1 : 12, such as from about 1 : 1 to about 1 :5, such as from about 1 :2 to about 1:4, such as about 1 :3. For example, the reaction mixture may include about 0.5 mmol of the organofluoride and about 1.5 mmol of the co-catalyst.

[0047] Suitable molar ratios of the organofluoride to the hydrogen source in the reaction mixture may be from about 1 :0.5 to about 1 :50, such as from about 1 :0.75 to about 1 :25, such as from about 1 : 1 to about 1 : 10, such as from about 1 :2 to about 1 :8, such as from about 1 :3 to about 1 :7, such as from about 1 :4 to about 1 :6, such as about 1 :5. For example, the reaction mixture may include about 0.5 mmol of the organofluoride and about 2.5 mmol of the hydrogen source.

[0048] Suitable molar ratios of the organic catalyst to co-catalyst in the reaction mixture may be from about 1 :60 to about 1 :6,000, such as from about 1 : 120 to about 1 :3,000, such as from about 1 :240 to about 1 : 1,500, such as from about 1 :300 to about 1 :900, such as from about 1 :400 to about 1 :800, such as from about 1 :500 to about 1 :700, such as about 1 :600. For example, the reaction mixture may include about 2.5 pmol of the catalyst and about 1.5 mmol of the co-catalyst.

[0049] Operation (b) of the process for converting the organofluoride to the conversion product includes exposing the reaction mixture to light to convert the organofluoride to the conversion product. Operation (b) may be performed in any suitable reactor such as a photoreactor. Any suitable photoreactor may be utilized. The light may be sourced from any suitable light source such as a light emitting diode (LED). Light sources may include those light sources emitting a wavelength of light (and / or a LED peak wavelength) in the visible range, or that is from about 300 nm to about 800 nm, or from about 350 nm to 750 nm, or from about 350 nm to about 450 nm, or from about 375 nm to about 430 nm, such as from about 395 nm to about 415 nm, or about 405 nm.

[0050] By exposure of the reaction mixture to the light, the organofluoride is converted to a crude product mixture. The crude product mixture may include component(s) of the crude product mixture, reaction product(s) of two or more components of the crude product mixture, a remainder balance of remaining starting component(s), or combinations thereof. The crude product mixture includes the conversion product (reduction product 102, e.g., the conversion product represented by formula (II)). The crude product mixture may optionally include unreacted starting materials, by-products, or combinations thereof. The crude product mixture may besubjected to purification techniques known in the art to obtain a purified form of the conversion product.Conversion of PFAS Compounds to Conversion Products

[0051] In an embodiment, which may be combined with other embodiments, a process for converting a perfluoroalkyl compound, a polyfluoroalkyl compound, or combinations thereof to a conversion product is provided. Perfluoroalkyl compounds and polyfluoroalkyl compounds are collectively referred to as PFAS or PFAS compounds. The process may include: (a) forming a reaction mixture comprising a PFAS compound, an organic catalyst, a co-catalyst, a hydrogen source, and an optional solvent; and (b) exposing the reaction mixture to light to convert the PFAS compound, under conversion conditions, to a conversion product. This process is a reduction reaction (a hydrodefluorination) to form a conversion product such as reduction product 102.

[0052] The PFAS compound is utilized as the substrate comprising a C-F bond, or the starting material, for the conversion. The PFAS compound includes two or more fluorine atoms. For example, the PFAS compound may include fluorine atoms covalently bonded to the same carbon atom. Additionally, or alternatively, the PFAS compound may include fluorine atoms covalently bonded to different carbon atoms. The PFAS compound may be represented by represented by formula (III):wherein: each of R3and R4of formula (III) are, independently, hydrogen, unsubstituted hydrocarbyl, substituted hydrocarbyl, or a functional group comprising at least one element from Group 13-17 of the periodic table of the elements; and at least one of R3or R4of formula (III) is the unsubstituted hydrocarbyl, substituted hydrocarbyl, or the functional group comprising at least one element from Group 13-17 of the periodic table of the elements.

[0053] R3and R4of formula (III) may be the same or different. Each of R3and R4of formula (III) may be, independently, linear or branched, saturated or unsaturated, cyclic or acyclic, monocyclic or polycyclic, aromatic or not aromatic. Each of R3and R4may be, independently, an R group described herein for R1or R2. For example, each of R1and R2may be, independently, an alkyl group having from 1 to 100 carbon atoms, such as from 1 to 20 carbon atoms, such as 3 to 10 carbon atoms; a cycloaliphatic grouphaving from 3 to 20 carbon atoms; an aromatic group having from 6 to 20 carbon atoms; or any combination thereof. Each of R3and R4of formula (III) may be, independently, a substituted hydrocarbyl such as an R group described herein for R1or R2. Each of R3and R4of formula (III) may be, independently, a functional group comprising at least one element from Group 13-17 of the periodic table of the elements such as an R group described herein for R1or R2.

[0054] At least one of R3or R4of formula (III) may be, independently, an unsubstituted hydrocarbyl having 1 to 20 carbon atoms or a substituted hydrocarbyl having 1 to 20 carbon atoms, or a functional group comprising at least one element from Group 13-17 of the periodic table of the elements. At least one of R3or R4of formula (III) may be, independently, a substituted hydrocarbyl comprising 1 to 20 carbons and a hydroxyl (-OH) group. At least one of R3or R4of formula (III) may be, independently, a substituted hydrocarbyl comprising 1 to 3 carbons and a hydroxyl (-OH) group.

[0055] At least one of R3or R4of formula (III) may, independently, comprise an ester represented by formula (V-A):wherein: R5of formula (V-A) is an unsubstituted hydrocarbyl comprising 1 to 6 carbon atoms; the wavy bond 1 ^ ) of formula (V-A) represents a connection to a difluoromethylene (-CF2-) group of the PFAS compound of formula (III); and the wavy bondof formula (V-A) represents a connection to the methylene (-CH2-) group of the conversion product of formula (IV).

[0056] At least one of R3or R4of formula (III) may, independently, comprise a substituted aryl or an unsubstituted aryl. Here, the aryl group may be directly connected to the carbon atom of the -CF2- group of formula (III), i.e., no atom between the carbon atom of the -CF2- group and a carbon atom of the aryl group. Alternatively, the aryl group may be indirectly connected to the carbon atom of the -CF2- group of formula (III), i.e., at least one atom (such as at least one carbon atom) between the carbon atom of the -CF2- group and a carbon atom of the aryl group.

[0057] At least one of R3or R4of formula (III) may, independently, comprise a carboxylic acid represented by formula (V-B):wherein the wavy bond ( ) of formula (V-B) represents a connection to a -CF2- group of the PF AS compound.

[0058] The conversion product formed from the conversion of the PF AS compound of formula (III) may be represented by formula (IV):wherein each of R3and R4in formula (IV) may be the same as or different from R3and R4of formula (III).

[0059] R3and R4in formula (IV) may differ from R3and R4of formula (III) when, for example, at least one of R3or R4of formula (III) may, independently, comprise a carboxylic acid represented by formula (V-B). Here, for example, the carboxylic acid may be converted to an ester such that at least one of R3or R4of formula (IV) is an ester. The ester may include an unsubstituted hydrocarbyl having 1 to 10 carbon atoms, such as from 2 to 8 carbon atoms, where the unsubstituted hydrocarbyl replaces the hydrogen atom of the carboxylic acid.

[0060] Suitable organic catalysts, co-catalysts, hydrogen sources, and optional solvents for the conversion of the PF AS compound to conversion products are described above for the process for converting the organofluoride of formula (I).

[0061] The process for converting the PF AS compound to the conversion product of formula (IV) may be performed under any suitable conversion conditions sufficient to form the conversion product.

[0062] Conversion conditions at operation (b) of the process for converting the PFAS compound may include the same or similar conversion temperatures and / or conversion pressures described above for the process for converting the organofluoride of formula (I). The components of the reaction mixture at operation (b) of the process to convert the PFAS compound may be mixed, stirred, or agitated by using suitable devices such as those described above. Components of the reaction mixture at operation (b) may be mixed, stirred, or agitated in the presence of a non-reactive gas, such as nitrogen (N2), argon (Ar), or combinations thereof, as described above.

[0063] The conversion of operation (b) of the process for converting the PFAS compound may be performed for any suitable conversion period. The conversion periodmay be about 200 hours or less, such as about 150 hours or less, such as about 120 hours or less, such as about 100 hours or less, such as about 60 hours or less, such as from about 1 hour to about 200 hours, such as from about 24 hours to about 150 hours, such as from about 48 hours to about 120 hours, such as from about 72 hours to about 96 hours. The conversion period is based on the length of exposure of the reaction mixture to the light.

[0064] Amounts of the organic catalyst in the reaction mixture may be based on the number of fluorine atoms in the PF AS compound in the reaction mixture. For example, an amount of organic catalyst in the reaction mixture per each fluorine atom of the PFAS compound in the reaction mixture may be from about 0.05 mol% to about 5 mol%, such as from about 0.1 mol% to about 2.5 mol%, such as from about 0.2 mol% to about 1.25 mol%, such as from about 0.3 mol% to about 0.8 mol%, such as about 0.5 mol%. For example, when the PFAS compound is 2,2,3,3,4,4,5,5-octafluoro-l,6- hexanediol (has 8 fluorine atoms), an amount of organic catalyst in the reaction mixture may be about 4.0 mol% (i.e., about 0.5 mol% catalyst for each fluorine atom).

[0065] Amounts of the co-catalyst (electron donor) in the reaction mixture may be based on the number of fluorine atoms in the PFAS compound in the reaction mixture. For example, an amount of co-catalyst in the reaction mixture per each fluorine atom of the PFAS compound in the reaction mixture may be from 0.1 mol% to about 11.0 mol%, such as from about 0.5 mol% to about 10.0 mol%, such as from about 0.5 mol% to about 3.0 mol%, such as from about 1.0 mol% to about 2.0 mol%, or from about 3.0 mol% to about 10.0 mol%, such as from about 5.0 mol% to about 8.0 mol%, such as from about 6.0 mol% to about 9.0 mol%.

[0066] Alternatively, amounts of the co-catalyst (electron donor) in the reaction mixture may be based on a molar ratio of the PFAS compound in the reaction mixture to the co-catalyst in the reaction mixture. For example, suitable molar ratios of the PFAS compound to the co-catalyst in the reaction mixture may be from about 1 : 1 to about 1 :20, such as from about 3: 1 to about 15: 1, such as from about 5: 1 to about 12: 1, such as about 7 : 1 to about 10: 1.

[0067] Amounts of the hydrogen source in the reaction mixture may be based on the number of fluorine atoms in the PFAS compound in the reaction mixture. For example, an amount (in equivalents) of hydrogen source in the reaction mixture per each fluorine atom of the PFAS compound in the reaction mixture may be from about 1.0 to about 20.0, such as from about 1.0 to about 10.0, such as from about 2.0 to about8.0, such as from about 4.0 to about 6.0, such as about 5.0, or from about 10.0 to about 20.0, such as from about 12.0 to about 18.0, such as from about 12.0 to about 18.0, such as from about 14.0 to about 16.0, such as about 15.0.

[0068] Operation (b) of the process for converting the PF AS compound includes exposing the reaction mixture to light to convert the PF AS compound to the conversion product represented by formula (IV). Operation (b) may be performed in any suitable reactor such as a photoreactor. Any suitable photoreactor may be utilized. The light may be sourced from any suitable light source such as a light emitting diode (LED). Light sources may include those light sources emitting a wavelength of light (and / or a LED peak wavelength) in the visible range, or that is from about 300 nm to about 800 nm, or from about 350 nm to 750 nm, or from about 350 nm to about 450 nm, or from about 375 nm to about 430 nm, such as from about 395 nm to about 415 nm, or about 405 nm.

[0069] By exposure of the reaction mixture to the light, the PFAS compound is converted to a crude product mixture. The crude product mixture may include component(s) of the crude product mixture, reaction product(s) of two or more components of the crude product mixture, a remainder balance of remaining starting component(s), or combinations thereof. The crude product mixture includes the conversion product (reduction product 102, e.g., the conversion product represented by formula (IV)). The crude product mixture may optionally include unreacted starting materials, by-products, or combinations thereof. The crude product mixture may be subjected to purification techniques known in the art to obtain a purified form of the conversion product.Conversion of Fluorinated Polymers

[0070] In an embodiment, which may be combined with other embodiments, a process for converting a fluorinated polymer to a conversion product is provided. The process may include: (a) forming a reaction mixture comprising a fluorinated polymer, an organic catalyst, a co-catalyst, a hydrogen source, and an optional solvent; and (b) exposing the reaction mixture to light to convert the fluorinated polymer, under conversion conditions, to a conversion product. This process is a reduction reaction (a hydrodefluorination) to form a conversion product such as reduction product 102.

[0071] The fluorinated polymer is utilized as the substrate comprising a C-F bond, or the starting material, for the conversion. The fluorinated polymer, may include one or more fluorine atoms. For example, the fluorinated polymer may include fluorineatoms covalently bonded to the same carbon atom. Additionally, or alternatively, the fluorinated polymer may include fluorine atoms covalently bonded to different carbon atoms. The fluorinated polymer may be represented by formula (VIII):wherein: D of formula (VIII) is an unsubstituted hydrocarbyl or a substituted hydrocarbyl; n of formula (VIII) is 0 or 1 (when n is 0, the fluorine atom is directly attached to the polymer backbone); Rbof formula (VIII) is hydrogen, unsubstituted hydrocarbyl, substituted hydrocarbyl, or a functional group comprising at least one element from Group 13-17 of the periodic table of the elements; and x of formula (VIII) is an integer from 1 to 1000, such as from 1 to 500, such as from 1 to 200, such as from 1 to 100, such as from 1 to 50.

[0072] Each of D or Rbof formula (VIII) may be, independently, linear or branched, saturated or unsaturated, cyclic or acyclic, monocyclic or polycyclic, aromatic or not aromatic. D of formula (VIII) may be an unsubstituted hydrocarbyl or a substituted hydrocarbyl such as an R group described herein for R1or R2of formula (I), among others. Rbof formula (VIII) may be hydrogen, an unsubstituted hydrocarbyl, a substituted hydrocarbyl, or a functional group comprising at least one element from Group 13-17 of the periodic table of the elements such as an R group described herein for R1or R2of formula (I), among others.

[0073] The conversion product produced from the conversion of the fluorinated polymer of formula (VIII) may be represented by formula (IX):wherein: D, Rb, and n of formula (IX) are described above for formula (VIII); x of formula (IX) is from 1 to 1000, such as from 1 to 500, such as from 1 to 200, such as from 1 to 100, such as from 1 to 50; y of formula (IX) is from 1 to 1,000, such as from1 to 500, such as from 1 to 200, such as from 1 to 100, such as from 1 to 50; x and y of formula (IX) are different; and Haof formula (IX) refers to a hydrogen atom that replaced the fluorine atom of formula (VIII) by the conversion.

[0074] Suitable organic catalysts, co-catalysts, hydrogen sources, and optional solvents for the conversion of fluorinated polymers to conversion products are described above for the process for converting the organofluoride of formula (I).

[0075] The process for converting the fluorinated polymer of formula (VIII) to the conversion product of formula (IX) may be performed under any suitable conversion conditions sufficient to form the conversion product.

[0076] Conversion conditions of operation (b) of the process may include the same or similar conversion temperatures and / or conversion pressures described above for the process for converting the organofluoride of formula (I). The components of the reaction mixture at operation (b) of the process to convert the fluorinated polymer may be mixed, stirred, or agitated by using suitable devices as described above. Components of the reaction mixture at operation (b) may be mixed, stirred, or agitated in the presence of a non-reactive gas, such as nitrogen (N2), argon (Ar), or combinations thereof, as described above.

[0077] The conversion of operation (b) of the process for converting the fluorinated polymer may be performed for any suitable conversion period. The conversion period may be about 200 hours or less, about 150 hours or less, about 100 hours or less, such as about 80 hours or less, such as about 50 hours or less, such as about 24 hours or less, such as about 20 hours or less, such as from about 1 hour to about 100 hours, such as from about 5 hours to about 80 hours, such as from about 10 hours to about 60 hours, such as from about 16 hours to about 48 hours. The conversion period is based on the length of exposure of the reaction mixture to the light.

[0078] Amounts of the organic catalyst in the reaction mixture may be based on the number of x repeating units in the fluorinated polymer in the reaction mixture. For example, an amount of organic catalyst in the reaction mixture per each x repeating unit of the fluorinated polymer in the reaction mixture may be from about 0.01 mol% to about 5.0 mol%, such as from about 0.01 mol% to about 1.0 mol%, such as from about 0.1 mol% to about 0.9 mol%, such as from about 0.3 mol% to about 0.7 mol%, or from about 1.0 mol% to about 5.0 mol%, such as from about 1.5 mol% to about 4.5 mol%, such as from about 2.5 mol% to about 3.5 mol%.

[0079] Amounts of the co-catalyst (electron donor) in the reaction mixture may be based on the number of x repeating units in the fluorinated polymer in the reaction mixture. For example, an amount of co-catalyst in the reaction mixture per each x repeating unit of the fluorinated polymer in the reaction mixture may be from about 0.5mol% to about 10.0 mol%, such as from about 0.5 mol% to about 3.0 mol%, such as from about 1.0 mol% to about 2.5 mol%, such as from about 1.5 mol% to about 2.0 mol%, or from about 3.0 mol% to about 10.0 mol%, such as from about 4.0 mol% to about 9.0 mol%, such as from about 5.5 mol% to about 7.0 mol%.

[0080] Amounts of the hydrogen source the reaction mixture may be based on the number of x repeating units in the fluorinated polymer in the reaction mixture. For example, an amount (in equivalents) of hydrogen source in the reaction mixture per each x repeating unit of the fluorinated polymer in the reaction mixture may be from about 1.0 to about 20.0, such as from about 1.0 to about 10.0, such as from about 3.0 to about 8.0, such as from about 4.5 to about 6.5, or from about 10.0 to about 20.0, such as from about 12.0 to about 18.0, such as from about 14.0 to about 16.0.

[0081] Operation (b) of the process for converting the fluorinated polymer includes exposing the reaction mixture to light to convert the fluorinated polymer to the conversion product. Operation (b) may be performed in any suitable reactor such as a photoreactor. Any suitable photoreactor may be utilized. The light may be sourced from any suitable light source such as a light emitting diode (LED). Light sources may include those light sources emitting a wavelength of light (and / or a LED peak wavelength) in the visible range, or that is from about 300 nm to about 800 nm, or from about 350 nm to 750 nm, or from about 350 nm to about 450 nm, or from about 375 nm to about 430 nm, such as from about 395 nm to about 415 nm, or about 405 nm.

[0082] The conversion of the fluorinated polymer may be tuned to control the relative proportion of C-F and C-Hain the conversion product. The controllable proportions may be based on conversion period, whereby longer reaction times result in a larger amount (%) of C-Harelative to C-F as determined by fluorine (19F)-NMR. For example, hydrodefluorination of poly(4-fluorostyrene) after 4 hours, 16 hours, and 48 hours may result in a C-F:C-Haof about 83: 17, 57:43, and 8:92, respectively. Complete defluorination of fluorinated polymers may be accomplished under suitable conditions. The ratio of C-F to C-Hain the conversion product, as determined by19F- NMR, may be any suitable ratio such as 0: 100, 5:95, 10:90, 20:80, 30:70, 40:60, 50:50, 60:40, 70:30, 80:20, 90: 10, or 95:5, or a ratio range that includes two of these ratios as endpoints.

[0083] By exposure of the reaction mixture to the light, the fluorinated polymer is converted to a crude product mixture. The crude product mixture may include component(s) of the crude product mixture, reaction product(s) of two or morecomponents of the crude product mixture, a remainder balance of remaining starting component(s), or combinations thereof. The crude product mixture includes the conversion product (reduction product 102, e.g., the conversion product of formula (IX)). The crude product mixture may optionally include unreacted starting materials, by-products, or combinations thereof. The crude product mixture may be subjected to purification techniques known in the art to obtain a purified form of the conversion product.Conversion of Organofluorides to Coupling Products

[0084] In an embodiment, which may be combined with other embodiments, a process for converting an organofluoride to a conversion product is provided. The process may include: (a) forming a reaction mixture comprising an organofluoride, an organic catalyst, a co-catalyst, a coupling partner, and an optional solvent; and (b) exposing the reaction mixture to light to convert the organofluoride, under conversion conditions, to a conversion product. This process is a cross-coupling reaction, for example, a borylation, phosphonylation, arylation, heteroarylation, sulfuration, or selenization, to form a conversion product, e.g., cross-coupling product 103. The crosscoupling product 103 formed by the process may include a newly formed C-B bond, C-P bond, C-C bond, C-S bond, or C-Se bond.

[0085] The organofluoride is utilized as the substrate comprising a C-F bond, or the starting material, for the conversion. The organofluoride may include one or more fluorine atoms. For example, the organofluoride may include fluorine atoms covalently bonded to the same carbon atom. Additionally, or alternatively, the organofluoride may include fluorine atoms covalently bonded to different carbon atoms. The organofluoride utilized for the process may be represented by formula (I).

[0086] The coupling partner, represented by A', comprises at least one element from Group 13-16 of the periodic table of the elements. A' may be a functional group comprising at least one element from Group 13-16 of the periodic table of the elements. A' may include O, N, Se, Te, P, As, Sb, S, B, Si, Ge, Sn, Pb, and the like, such as C(O)R*, C(C)NR*2, C(O)OR* (e.g., ester), NR*2, OR*, SeR*, TeR*, PR*2, AsR*2, SbR*2, SR*, SOX(where x = 2 or 3), BR*2, SiR*3, GeR*3, SnR*3, PbR*3, and the like, where R* is, independently, hydrogen or unsubstituted hydrocarbyl, or where at least one heteroatom has been inserted within the unsubstituted hydrocarbyl. A' may include boron (B), carbon (C), phosphorous (P), sulfur (S), selenium (Se), or combinations thereof.

[0087] The conversion product formed from the conversion of the organofluoride of formula (I) by the cross-coupling reaction may be represented by formula (VI):wherein: A" of formula (VI) comprises the at least one element from Group 13-16.

[0088] A" of formula (VI) may include one or more of those elements of Group 13- 16 described above for A', such as B, C, P, S, Se, or combinations thereof. A" may be a boron-containing functional group, a phosphorous containing functional group, an aryl -containing functional group, a heteroaryl -containing functional group, a sulfur- containing functional group, or a selenium-containing functional group.

[0089] For borylation reactions, the coupling partner A' includes boron or a boron- containing group. Illustrative, but non-limiting, examples, of a coupling partner comprising boron or a boron-containing group may include, but are not limited to, bis(pinacolato)diboron (B2Pin2), bis(2,4-dimethylpentane-2,4-glycolato)diboron, bis(neopentyl glycolato)diboron (B2(neop)2), or combinations thereof. For phosphonylation reactions, the coupling partner A' includes phosphorous or a phosphorous-containing group. A non-limiting example of a coupling partner comprising phosphorous or a phosphorous-containing group may include, but is not limited to, triethyl phosphite (P(OEt)3).

[0090] For arylation reactions, the coupling partner A' includes carbon or a carbon- containing group, such as an aryl group. The aryl group is a hydrocarbon ring system comprising hydrogen, 5 to 30 carbon atoms (such as 6 to 14 carbon atoms), and at least one aromatic ring. The aryl group may be a monocyclic, bicyclic, or tricyclic system and which may include spiro ring systems. Aryl groups may be, or be derived from, phenyl, naphthyl, acenaphthylene, anthracene, azulene, benzene, 6,7,8,9-tetrahydro- 5H-benzo[7]annulene, fluorene, as-indacene, s-indacene, indane, indene, naphthalene, phenalene, and phenanthrene. The aryl group may be unsubstituted or substituted with one or more substituents. When substituted, the one or more substituents may, independently, include an unsubstituted hydrocarbyl, a substituted hydrocarbyl, or a functional group comprising at least one element from Groups 13-17. Suitable unsubstituted hydrocarbyls, substituted hydrocarbyls, and functional groups comprising at least one element from Groups 13-17 may include those described herein for R1or R2of formula (I), among others.

[0091] For heteroarylation reactions, the coupling partner A' includes a heteroaryl group as described herein. Illustrative, but non-limiting, examples of heteroaryl groups may include pyrrolidinyl, pyridinyl, furanyl, thiophenyl, imidazolidinyl, or oxazolidinyl, among others. The heteroaryl group may be unsubstituted or substituted with one or more substituents. When substituted, the one or more substituents may, independently, include an unsubstituted hydrocarbyl, a substituted hydrocarbyl, or a functional group comprising at least one element from Groups 13-17. Suitable unsubstituted hydrocarbyls, substituted hydrocarbyls, and functional groups comprising at least one element from Groups 13-17 may include those described herein for R1or R2of formula (I), among others. Illustrative, but non-limiting, examples, of a coupling partner comprising a heteroaryl group may include, but are not limited to, N- methylpyrrole, 1 -phenylpyrrole, 1 -benzyl- IH-pyrrole, or combinations thereof.

[0092] For sulfuration reactions, the coupling partner A' includes sulfur or a sulfur- containing group. The coupling partner may include SR*2, where each R* is, independently, an unsubstituted hydrocarbyl or a substituted hydrocarbyl. Suitable unsubstituted hydrocarbyls and substituted hydrocarbyls may include those described herein for R1or R2of formula (I), among others. The coupling partner may include, but is not limited to, dimethyldisulfide (S2Me2). For selenization reactions, the coupling partner A' includes selenium or a selenium-containing group. The coupling partner may include SeR*2, where each R* is, independently, an unsubstituted hydrocarbyl or a substituted hydrocarbyl. Suitable unsubstituted hydrocarbyls and substituted hydrocarbyls may include those described herein for R1or R2of formula (I), among others. The coupling partner may include, but is not limited to, dibutyl diselenide (Se2nBu2).

[0093] Table A shows example coupling partners A', functional group A" of the conversion product, and the conversion product of formula (VI) for the cross-coupling reaction.Table A

[0094] In Table A, the wavy bond represents a connection to the methylene carbon (-CR1R2-) of the conversion product represented by formula (VI). Z" of formula (VI- E) may be an aryl, optionally substituted by one or more substituents comprising an unsubstituted hydrocarbyl, a substituted hydrocarbyl, or a functional group comprisingat least one element from Groups 13-17 of the periodic table of the elements; or Z" of formula (VI-E) may be heteroaryl, optionally substituted by one or more substituents comprising an unsubstituted hydrocarbyl, a substituted hydrocarbyl, or a functional group comprising at least one element from Groups 13-17 of the periodic table of the elements. Z" is derived from the coupling partner Z' from reaction of the coupling partner Z' with an organofluoride. X of formula (VI-F) is S or Se; and RAof formula (VI-F) is an unsubstituted hydrocarbyl or a substituted hydrocarbyl.

[0095] Suitable organic catalysts, co-catalysts, and optional solvents for the conversion of the organofluoride to conversion products (cross-coupling products 103) are described above for the process for converting the organofluoride of formula (I).

[0096] The process for converting the organofluoride of formula (I) to the crosscoupling product represented by formula (VI) may be performed under any suitable conversion conditions sufficient to form the conversion product.

[0097] Conversion conditions of operation (b) of the process for converting the organofluoride to the cross-coupling product may include the same or similar conversion temperatures and / or conversion pressures described above for the process for converting the organofluoride of formula (I). The components of the reaction mixture at operation (b) of the process to convert the organofluoride to the crosscoupling product may be mixed, stirred, or agitated by using suitable devices as described above. Components of the reaction mixture at operation (b) may be mixed, stirred, or agitated in the presence of a non-reactive gas, such as nitrogen (N2), argon (Ar), or combinations thereof, as described above.

[0098] The conversion of operation (b) of the process for converting the organofluoride to the cross-coupling product may be performed for any suitable conversion period. The conversion period may be about 200 hours or less, such as about 100 hours or less, such as about 80 hours or less, such as about 50 hours or less, such as about 24 hours or less, such as about 20 hours or less, such as from about 1 hour to about 100 hours, such as from about 5 hours to about 80 hours, such as from about 10 hours to about 60 hours, such as from about 16 hours to about 48 hours. The conversion period is based on the length of exposure of the reaction mixture to the light.

[0099] Suitable molar ratios of the organic catalyst to the organofluoride in the reaction mixture may be from about 1 :6 to about 1 : 1,000, such as from about 1 : 10 to about 1 :800, such as from about 1 :20 to about 1 :500, such as from about 1 :30 to about 1 :300, such as from about 1 :40 to about 1 :200, such as from about 1 :50 to about 1 : 120,such as from about 1 :60 to about 1 : 100, such as about 1 :80. For example, the reaction mixture may include about 5 mmol to about 7.5 pmol of the organic catalyst and about 0.5 mmol of the organofluoride.

[0100] Suitable molar ratios of the organofluoride to the co-catalyst in the reaction mixture may be from about 1 :0.1 to about 1 :30, such as from about 1 :0.5 to about 1 : 18, such as from about 1 :0.8 to about 1 : 12, such as from about 1 : 1 to about 1 :5, such as from about 1 :2 to about 1 :4, such as about 1 :3. For example, the reaction mixture may include about 0.5 mmol of the organofluoride and about 1.5 mmol of the co-catalyst.

[0101] Molar ratios of the organofluoride to the coupling partner (reactant) in the reaction mixture may depend on the reactivity of the coupling partner in the reaction mixture. For example, a lower number of equivalents of B2Pin2 may be used relative to N-methylpyrrole. Suitable molar ratios of the organofluoride to the coupling partner (reactant) in the reaction mixture may be from about 1 : 1 to about 1 :200, such as from about 1 : 1.25 to about 1 :150, such as from about 1 : 1.5 to about 1 : 100, such as from about 1 : 1.75 to about 1 :50, such as from about 1 :2 to about 1 :30, such as from about 1 :2.5 to about 1 :20, such as about 1 :3 to about 1 : 10.

[0102] Suitable molar ratios of the organic catalyst to co-catalyst in the reaction mixture may be from about 1 :60 to about 1 :6,000, such as from about 1 : 120 to about 1 :3,000, such as from about 1 :240 to about 1 : 1,500, such as from about 1 :300 to about 1 :900, such as from about 1 :400 to about 1 :800, such as from about 1 :500 to about 1 :700, such as about 1 :600. For example, the reaction mixture may include about 2.5 pmol of the catalyst and about 1.5 mmol of the co-catalyst.

[0103] Operation (b) of the process for converting the organofluoride to the crosscoupling product includes exposing the reaction mixture to light to convert the organofluoride to the conversion product. Operation (b) may be performed in any suitable reactor such as a photoreactor. Any suitable photoreactor may be utilized. The light may be sourced from any suitable light source such as a light emitting diode (LED). Light sources may include those light sources emitting a wavelength of light (and / or a LED peak wavelength) in the visible range, or that is from about 300 nm to about 800 nm, or from about 350 nm to 750 nm, or from about 350 nm to about 450 nm, or from about 375 nm to about 430 nm, such as from about 395 nm to about 415 nm, or about 405 nm.

[0104] By exposure of the reaction mixture to the light, the organofluoride is converted to a crude product mixture. The crude product mixture may includecomponent(s) of the crude product mixture, reaction product(s) of two or more components of the crude product mixture, a remainder balance of remaining starting component(s), or combinations thereof. The crude product mixture includes the conversion product (cross-coupling product 103, e.g., the conversion product represented by formula (VI)). The crude product mixture may optionally include unreacted starting materials, by-products, or combinations thereof. The crude product mixture may be subjected to purification techniques known in the art to obtain a purified form of the conversion product.

[0105] FIG. 2 shows a proposed, and non -limiting, mechanism for a photoredox- catalyzed dehalogenation of fluorobenzene according to at least one embodiment of the present disclosure. (nBu refers to butyl, LED refers to light-emitting diodes, PET refers to photoinduced electron transfer, PCET refers to proton-coupled electron transfer, and PTZET refers to proton transfer / electron transfer). Specifically, the hypothesized mechanistic outline for the hydrodefluorination of fluorobenzene (Ph-F) is depicted. First, a ring-opened intermediate (BPI-RO) with an amide and a carboxylate functional group may be formed through a hydrolyzing reaction under dark conditions. Irradiation of BPI-RO may form the excited-state BPI-RO*, which may be reductively quenched by F to form the open-shell intermediate BPI-RO' . Thereafter, a second photoexcitation event may form a strongly reducing excited-state radical anion species BPI-RO' *, which may remove a hydrogen atom from a hydrogen source (H-source, e.g., tert-AmylOH or THF, among others) to form a closed-shell species BPI-RO-H . After photoexcitation, BPI-RO-H * may be strong enough to reduce fluorobenzene by an outer-sphere electron transfer event. The Ph-F' species may fragment to form a carbon-centered radical that may gain a hydrogen atom to form benzene as the reduction product or be reacted with a coupling partner. Investigations into the mechanism are described in the Examples.

[0106] The following examples are put forth so as to provide those of ordinary skill in the art with a complete disclosure and description of how to make and use embodiments of the present disclosure, and are not intended to limit the scope of embodiments of the present disclosure. Efforts have been made to ensure accuracy with respect to numbers used but some experimental errors and deviations should be accounted for.Examples

[0107] Non-limiting examples of processes for activating C-F bonds using an organic photoredox catalyst were performed. Non-limiting examples of processes for converting a substrate comprising a C-F bond (a fluorinated organic molecule) to a conversion product were also performed.

[0108] All experiments were performed under N2 atmosphere by using standard Schlenk techniques or in a glove box, if not stated otherwise. All air- and moistureinsensitive reactions were carried out under ambient atmosphere and monitored by thin- layer chromatography. Concentration under reduced pressure was performed by rotary evaporation at 25-40°C at an appropriate pressure. Purified compounds were further dried under a high vacuum. Yields refer to purified and spectroscopically pure compounds. All air- and moisture-sensitive manipulations were performed using oven- dried glassware (120°C for a minimum of 24 hours) and standard Schlenk techniques under an atmosphere of N2.

[0109] The photoreactor was custom designed. All light-emitting diodes (LEDs) used were purchased from LED Engin and full emission spectra, as well as peak wavelength shift vs. temperature data, are available online in the respective manufacturer datasheets. In the photoreactor, blue LEDs were run at 700mA and a forward voltage of 13.5 V. The mini fan (Manufacturer Product Number: THA0412AD) was from Delta Electronics, Inc. The rest of the materials were produced in our laboratory using a 3D printer. The distance from the LED emitter surface to the vial is 5.0 mm (small scale reaction) and 10.0 mm (large-scale reaction).

[0110] Photoreactor specifications. The photoreactor included a Delta Electronics 60 mm fan (51.7 cfm airflow at 750 mA, 12 V), a Delta Electronics 40 mm fan (20.56 cfm airflow at 430 mA, 12 V), a Mean Well fan power supply (12 V, 240 W, switching), a Cincon LED power supply (18 V, 150 W, switching), a LEDdynamics LED driver (Output: Input V - 2.5 V, 700 mA) a Wakefield heatsink (2.75” diameter, 3” thick aluminum), a 3D-printed reactor chamber (fits 40 mm fan, 65 mm heatsink), and a 3D- printed vial holder (0.5 dram, 1.5 dram, or 20mL).

[0111] Light source specifications for six different light sources. Within each of light sources (l)-(6), “LEDPW” refers to LED peak wavelength and “LF” refers to luminous flux: (1) LEDPW (365 nm) and LF (3.3W at 700mA, 15.5V); (2) LEDPW (395 nm) and LF (4.1W at 700mA, 15.5V); (3) LEDPW (405 nm) and LF (4.1W at 700mA, 13.5V); (4) LEDPW (456 nm) and LF (4.1W at 700mA, 13.5 V); (5) LEDPW(Cool White) and LF (4.1W at 700mA, 13.5V); (6) LEDPW (523 nm) and LF (4.1W at 700mA, 13.5 V).

[0112] THF, DMF, DCM, and toluene were dried using a solvent purification system. Dry DMac, MeCN, DMSO, acetone, MeOH, ethyl acetate (EtOAc), EtOH, iPrOH, pyridine, / c / V-Amyl alcohol, toluene, and n-Hexane were purchased from Acros Organics, degassed, and purged with argon prior to use. All solvents were stored in the glovebox. Deuterated solvents were ordered from Oakwood Chemical and stored over molecular sieves.

[0113] The BPI catalyst {2-(2-ethylhexyl)-6,8,ll-tris(4-methoxyphenyl)-lH- peryleno[l,12-efg] isoindole-1, 3(2H)-dione) was made according to the following procedure. To a 100 mL storage flask was added 1 -(cyclohexa- 1,4-dien-l-yl )propan-2- ol (0.23 g, 0.32 mmol, 1.0 eq.) and 4-methoxyphenylboronic acid (0.30 g, 6.0 eq.). The storage flask was then moved into a N2-filled glovebox where Pd(PPhs)4 (0.06 g, 0.005 mmol, 15 mol%) was added. 25mL of THF was then added and the storage tube removed from the glovebox. 6.2 mL of 2M aqueous K2CO3 was then added. The reaction was then heated to 100°C for 24 h. DCM was added to the mixture and washed with water 3 times, then brine, and dried with MgSCU BPI has the structure of formula (VII-B) described herein.

[0114] All substrates and reagents were used as received from commercial suppliers or prepared according to published procedures unless otherwise stated. nBu4NF, Me4N0H, Et4NF, Me4NF, nBu4NCl, nBu4NBr, and tert-AmylOH were stored in the glovebox. Fluorinated polymers were synthesized using known literature procedures. 4A molecular sieves may be added to the purchased nBu4NF and then stored in the fridge in a glovebox.

[0115] Analytical thin layer chromatography was performed using pre-coated Merck glass backed silica gel plates (Silicagel 60 F254). Visualization was achieved using ultraviolet light (254 nm) and chemical staining with ceric ammonium molybdate or basic potassium permanganate solutions as appropriate. Flash column chromatography was undertaken on Fluka or Material Harvest silica gel (230-400 mesh) under a positive pressure of air. Flash chromatography purification system (Combiflash® Rf 150) was also used to purify the products.

[0116] NMR spectra were recorded at ambient temperature on either a BrukerUltrashield-400 (400 MHz) spectrometer, a Varian 400 MR (400 MHz) spectrometer or an Agilent Inova 400 (400 MHz) spectrometer in the Colorado State UniversityAnalytical Resources Core (ARC). Gas chromatography (GC) analyses were performed on a Trace 1310 chromatograph with a 29 m HP5 column. GC yields and conversions are based on a calibrated area of mesitylene as the internal standard. 'H-NMR yields and conversions are based on a calibrated area of 1,3,5-trimethoxybenzene as internal standard. High Resolution Mass spectroscopy (HRMS) analysis was performed on a 6224 Time-of-Flight LC / MS (Agilent) at Colorado State University Central Instrument Facility. Ultraviolet-visible (UV-Vis) spectroscopy was performed on a Cary 5000 spectrophotometer. All samples were analyzed in 1.0 cm pathlength quartz cuvettes. Emission spectra were collected on an SLM 8000C fluorimeter. Emission spectra are affected by the instrumental setup in addition to the signal from the molecule alone. Because of this, the collected data was corrected for the instrument-specific response by application of a correction file associated with a specific configuration of the fluorimeter. The data collected herein utilized a configuration in which the slits before and after each monochromator were set to 2 nm, and so a correction file generated under those conditions was used to correct the data. TCSPC measurements were made using a DeltaFlex Modular Fluorescence Lifetime System from Horiba Scientific. A Horiba NanoLED-405L was used as the excitation source (402 nm center- wavelength [CWL], c. 220 ps full-width at half maximum [FWHM]). Temperatures were measured with a built-in digital temperature sensor in the Horiba device. Temperature was controlled by a Quantum Northwest TC-1 temperature control unit coupled with an aquarium pump submerged in a reservoir, and a jacketed sample holder. Cyclic voltammograms were obtained using a Gamry electrochemical analyzer with an Ag / AgNO3 (0.01 M in acetonitrile) reference electrode and tetrabutyl ammonium hexafluorophosphate (TBAPFe) (0.1 M in DMAc) as the electrolyte for the working electrode. All samples were analyzed in DMAc at a concentration between 0.06 mM and 1 mM (depending on solubility) at a total volume of 25.0 mL and were sparged with nitrogen for 15 minutes before data collection. Platinum was used for the working and counter electrodes. Analysis was conducted at scan rates of 100 mV / s, 80 mV / s, 50 mV / s, and 20 mV / s with 7 cycles each. Data from the 6th cycle was analyzed unless otherwise noted. All voltammograms were corrected using the El / 2 of ferrocene as a reference. Molecular weights were determined by Gel Permeation Chromatography (GPC) coupled with multi-angle light scattering (MALS) using an Agilent HPLC fitted with one guard column, three PL-gel 5 pm MIXED-C gel permeation columns, a Wyatt TechnologyTrEX differential refractometer, and a Wyatt Technology mini-DAWN TREOS light scattering detector (MALS).Example 1 : Hydrodefluorination of OrganofluoridesExample 1.1: Investigation of light sources, hydrogen sources, and electron donors

[0117] In a glovebox, a 5 mL glass vial containing a stirring bar was sequentially charged with photocatalyst BPI (2.5 pmol, 0.5 mol%), electron donor (nBu4NF, 1.5 mmol, 3.0 equiv.), and solvent (THF, 1.5 mL). The mixture was stirred for 20 minutes at 23°C. Subsequently, the starting materials (SI, 0.5 mmol) and hydrogen source (tert- AmylOH, 2.5 mmol, 5.0 equiv.) were added in one portion. The glass vial was placed into the photoreactor (405 nm LED) and stirred for 16 h. The temperature was kept at approximately 23 °C through cooling with six mini fans. After the specified time, the mixture was diluted with EtOAc and analyzed by GC using mesitylene as internal standard. Scheme Sl-1 shows hydrodefluorination of fluorobenzene SI.Scheme Sl-1

[0118] Various light source wavelengths were tested and included (in the parentheses after each wavelength includes the conversion of SI (%) and then the yield of S2 (%)): 365 nm (5%; 4%), 395 nm (99%; 87%), 405 nm (99%; 88%); 427 nm (40%; 17%), 456 nm (57%; 45%), cool white (0%; 0%), and 523 nm (0%; 0%). The reaction conditions for light source testing included: SI (0.5 mmol), BPI (0.5 mol%), nBu4NF (1.5 mmol, 1.5 mL, 1.0M in THF), tert-AmylOH (2.5 mmol, 5.0 equiv.), r.t. (23°C), 16 h. Conversion and yields were determined by GC (internal standard: mesitylene).

[0119] Various hydrogen sources (proton sources) were also tested. These included the following hydrogen sources (in the parentheses after each hydrogen source includes the amount of hydrogen source, the conversion of SI (%), and then the yield of S2 (%)): H2O (15.2 equiv.; 0%; 0%); HSCH2CO2Me (5.0 equiv.; 0%; 0%); DMF (12.5 equiv.; 16%; 14%); DMSO (12.3 equiv.; 0%; 0%); MeOH (5.0 equiv.; 37%; 33%); EtOH (5.0 equiv.; 57%; 42%); zPrOH (5.0 equiv.; 68%; 65%); ZczV-AmylOH (5.0 equiv.; 99%; 88%); Glycerol (5.0 equiv.; 20%; 17%); Benzyl alcohol (5.0 equiv.; 19%; 11%); MeOH (14.8 equiv.; 98%; 85%); MeOH (10.0 equiv.; 96%; 81%); EtOH (10.0 equiv.; 99%; 84%); zPrOH (10.0 equiv.; >99%; 83%). The reaction conditions for hydrogen sourcetesting was the same as the light source testing except that a 405 nm LED was used and the hydrogen source and amount thereof differed.

[0120] Various electron donors (a co-catalyst) were tested. These included the following electron donors (in the parentheses after each electron donor includes whether it is soluble, the conversion of SI (%), and then the yield of S2 (%)): Et3N (soluble; 0%; 0%); iPr2NEt (soluble; 0%; 0%); DIPEA (soluble; 0%; 0%); DABCO (soluble; 0%; 0%); nBu4NF (soluble; 99%; 88%); nBu4NCl (slightly soluble; <5%; 3%); nBu4NBr (insoluble; 0%; 0%); nBu4NI (insoluble; 0%; 0%); nBu4NPFe (insoluble; 0%; 0%); nBu4N(HSO4) (insoluble; 0%; 0%); nBu4NF(OCOCH3) (insoluble; 0%; 0%); nBu4N(SCN) (insoluble; 0%; 0%); nBu4N(OCOC6Hs) (insoluble; 0%; 0%); nBu4N(CF3SO3) (insoluble; 0%; 0%); Et4NF (soluble; 80%; 67%); Me4NF (insoluble; 11%; <3%); Me4N0H (soluble; 77%; 56%). The reaction conditions for the electron donor testing included: SI (0.5 mmol), BPI (0.5 mol%), electron donors (1.5 mmol, 3.0 equiv.), tert-AmylOH (2.5 mmol, 5.0 equiv.), THF (1.5 mL), r.t. (23°C), 16 h, 405 nm LED. Conversion and yields were determined by GC (internal standard: mesityl ene).Example 1.2: Hydrodefluorination of alkyl / aryl fluorides

[0121] For this example, the organofluoride is an alkyl or aryl fluoride. Scheme Sl- 2 shows an example reaction diagram for dehalogenation of alkyl and aryl fluorides.Scheme SI -2 1 p BPI, nBu4NF, t-AmylOH pi |_|"R2 THF, r.t., 405 nm LED "p2

[0122] General procedure for the dehalogenation of alkyl and aryl fluorides (GP- 1): In a glovebox, a 5 mL glass vial containing a stirring bar was sequentially charged with BPI catalyst (2.5 pmol, 0.5 mol%) and nBu4NF (1.5 mmol, 1.5 mL, 3.0 equiv., 1.0M in THF). The mixture was stirred for 20 minutes at 23°C, and the color changed from orange to light green. Subsequently, an organofluoride (0.5 mmol) and tert- AmylOH (2.5 mmol, 5.0 equiv.) were added in one portion. The glass vial was placed into the photoreactor (405 nm LED) and stirred for corresponding time. The temperature was kept at approximately 23°C through cooling with six mini fans. The reaction was generally run between 16 and 48 hours. After reaction, the crude mixture was purified by column chromatography on silica gel to afford the desired products. Highly volatile or lower boiling point fluorinated substrates were added outside theglove box using a syringe. A CombiFlash Rf Flash Chromatography System was used to purify the product (40 g HP Silica was used).

[0123] Table 1-2 shows selected conversion products using hydrodefluorination processes described herein. HArefers to a hydrogen atom that replaced the fluorine atom of the organofluoride by using the hydrodefluorination. Table 1-2 also shows the % yield (by GC measurements) and the reaction time for hydrodefluorination. Boc refers to tert-butoxycarbonyl; Ph refers to phenyl; p-, m-, and o- refer to para, meta, and ortho positions, respectively, on the aromatic ring.Table 1-2

[0124] Overall, Table 1-2 indicates the broad success of C-F bond activation with the catalyst system and the conversion of organofluorides according to embodiments described herein. Reactions were performed under inert atmosphere in a nitrogen filled glovebox but may also be performed using standard Schlenk techniques. A variety of both electron-poor and electron-rich aryl fluorides possessing different functional groups (e.g., free alcohol, carboxylic acid, amine, and nitrile) were tolerated by the catalytic system and afforded the corresponding products (S3 to S10) in good yieldswhile no Birch-type arene reduction products were observed under these reaction conditions. Furthermore, this methodology extended to alkyl fluorides and was determined to be efficient in the defluorination of primary, secondary, and tertiary alkyl fluorides in good to high yields (SI 1 to SI 6). This reactivity was also efficient with Cl or Br-based organohalides (not shown). In addition, polyfluorinated compounds were successfully reduced by embodiments described herein and were efficiently converted to hydrodefluorination products (SI 7 to S24). Moreover, several natural products and drug derivatives were also amenable to hydrodefluorination to the corresponding products (S25 to S28) in good yield.Example 2: Hydrodefluorination of perfluoroalkyl and polyfluoroalkyl substances (PFAS)

[0125] Scheme S2-1 shows a general reaction diagram for the hydrodefluorination of PFAS.Scheme S2-1BPI (x mol%) nBu NF (y equiv.)

[0126] General Procedure for the hydrodefluorination of PFAS compounds (GP- 2): In a glovebox, a 5 mL glass vial containing a stirring bar was sequentially charged with BPI (catalyst was used according to the fluorine atom in the compounds, each fluorine atom corresponds to 0.5 mol% catalyst), nBu4NF (the amount of electron donor was adjusted for different types of PFAS compounds) and MeOH (1.5 mL). The mixture was stirred for 20 minutes at 23 °C, and the color changed from orange to light green. Subsequently, the PFAS compound (0.2 mmol) were added outside the glovebox. The glass vial was placed into the photoreactor (405 nm LED) and stirred for corresponding time. The temperature was kept at approximately 23 °C through cooling with six mini fans. After reaction, the mixture was diluted with acetone and analyzed by GC using mesitylene as internal standard. The high boiling point product 4- butylbenzonitrile S41 (from 4-(perfluorobutyl)benzonitrile starting material) and butyl octanoate S44 may be purified by column chromatography on silica gel. Highly volatile or lower boiling point PFAS compounds were added outside the glove box using a syringe under nitrogen. 4-(perfluorobutyl)benzonitrile and perfluorooctanoic acid (PFOA) may be added in the glovebox. Due to the solubility of the BPI catalyst, betterresults may be found when the amount of methanol added is not higher than THF, otherwise the catalyst may be precipitated.

[0127] Table 2-1 shows selected conversion products from hydrodefluorination processes of PFAS compounds described herein, % yield (by GC), and the reaction time. Harefers to a hydrogen atom that replaced the fluorine atom of the PFAS compound by using hydrodefluorination described herein. PFBA refers to methyl perfluorobutyrate, PFPeA refers to methyl perfluoropentanoate, PFHxA refers to methyl perfluorohexanoate.Table 2-1

[0128] Overall, Table 2-1 indicates that PF AS may be degraded according to embodiments described herein. Using methanol as the protic solvent, several PF AS, including perfluorooctanoic acid (PFOA), could be converted to the defluorinatedproducts (S36-S42) in high yield, representing a mild reaction methodology for breaking down these persistent chemicals. Interestingly, and as shown in Scheme S2- 2, the carboxylic acid PFOA (S42) may be defluorinated to the / / -butyl ester through additional reaction with nBu4NF. Scheme S2-2 shows the general reaction diagram for the hydrodefluorination of PFOA (S42) to yield methyl octanoate S43 and butyl octanoate S44. All fluorine atoms in PFOA were converted to hydrogen atoms.Scheme S2-2

[0129] The reaction shown in Scheme S2-2 followed GP-2 with modifications. According to the GP-2, BPI (15.2 mg, 4.0 mol%), perfluorooctanoic acid (207 mg, 0.5 mmol), nBu4NF (2.5 mmol, 2.5 mL, 5.0 equiv., 1.0M in THF) and MeOH (0.5 mL) were reacted. After being stirred for 48 h, the reaction mixture was moved back into the glovebox, where more BPI (15.2 mg, 4.0 mol%), nBu4NF (2.5 mmol, 2.5 mL, 5.0 equiv., 1.0M in THF) and MeOH (0.5 mL) were added. The vial was then removed from the glovebox and placed back into the photoreactor. After the reaction, mesityl ene (60 mg, 0.5 mmol) was added as internal standard to determine the yield.

[0130] Given that the reaction may be implemented with small molecules, larger fluorinated polymers were tested. For example, poly(4-fluorostyrene) (10 mmol) undergoes complete hydrodefluorination to conversion product S46 using, for example, BPI (1.5 mol%), nBu4NF (4.0 equiv.), and tert-AmylOH (5.0 equiv.) with 405 nm LED at room temperature for about 30-96 hours. Gel permeation chromatography (GPC) data taken before and after the reaction demonstrated the lack of chain scission accompanying polymer hydrodefluorination. Notably, monitoring the reaction profile revealed that embodiments described herein may be utilized to controllably tune the polymer fluorine content by reaction time shown in select examples below.Example 3 : Hydrodefluorination of fluorinated polymers

[0131] A variety of fluorinated polymer derivatives may be transformed to targeted hydrodefluorination products using embodiments described herein. Scheme S3-1 shows an example reaction diagram for hydrodefluorination of fluorinated polymers.Scheme S3-1

[0132] General Procedure for hydrodefluorination of fluorinated polymers (GP-3): In a glovebox, a 5 mL glass vial containing a stirring bar was sequentially charged with BPI (5.0 pmol, 1.0 mol%) and nBu4NF (1.5 mmol, 1.5 mL, 3.0 equiv., 1.0M in THF). The mixture was stirred for 20 minutes at 23 °C, and the color changed from orange to light green. Subsequently, the fluorinated polymer (0.5 mmol, fluorinated polymer was used according to the repeating unit of polymers) and / c / V-AmylOH (2.5 mmol, 5.0 equiv.) were added in one portion. The glass vial was placed into the photoreactor (405 nm LED) and stirred for the corresponding time. The temperature was kept at approximately 23 °C through cooling with six mini fans. After reaction, the solution was pipetted into stirring methanol to precipitate polymer and collected via Buchner filtration with nylon filter paper to yield the dehalogenation polymers. Collected polymer is placed on high vacuum overnight before characterization. The ratio of the product units was determined by19F-NMR.

[0133] Table 3-1 shows selected conversion products from reaction of various fluorinated polymers under conditions to controllably tune the relative amount of C-F and C-H in the hydrodefluorination products. It is noted that complete defluorination may be accomplished under suitable conditions. Harefers to a hydrogen atom that replaced the fluorine atom of the fluorinated polymer by using the hydrodefluorination. The % of C-F and C-Hashown in Table 3-1 refers to molar amounts in the hydrodefluorination products. Conversion products from the controllable hydrodefluorination shown in Table 3-1 — S46-a, S46-b, S47, and S48 — are from various poly(4-fluorostyrene); S49 is from fluorinated polyacrylate; and S50 and S51 are from different poly(fluorostyrene)-derived copolymers — poly(4-fluorostyrene-co- acrylonitrile) and poly(4-fluorostyrene-co-ester). For S46-a and S46-b, 1 mmol and 10 mmol refer to the amount of fluorinated polymer in the reaction mixture.Table 3-1 : Hydrodefluorination products by a controllable hydrodefluorinationExample 4: Cross-Coupling Reactions - Borylation, Phosphonylation, Arylation, Heteroaryl ati on. Sulfuration, and Selenization of Organofluorides

[0134] Here, the inventors investigated cross-coupling reactions by intercepting the carbon-centered radical generated from a fluoride reduction. By including a coupling partner (reactant) instead of a hydrogen source, a cross-coupling reaction may be performed. Such cross-coupling reactions include borylation, phosphonylation, arylation, heteroaryl ati on, sulfuration, and selenization. Scheme S4 shows the general scheme for the cross-coupling reactions.Scheme S4R1F BPI, nBu4NF R1A"Y + A _ 2 YR2solvent, r.t., LED R2

[0135] For this example, the cross-coupling reaction generally included 1 equiv. of the organofluoride, 1 mol% to 1.5 mol% of catalyst BPI, 2.5 equiv. of the coupling partner A', 3 equiv. of the co-catalyst (nBu4NF), and a solvent. The amount of coupling partner, catalyst, and co-catalyst may vary when there are more than one fluorine atom present on the organofluoride.Example 4-1: Borylation Reaction. Scheme S4-1 shows an example reaction diagram for the borylation of aryl fluorides.Scheme S4-1R1 F BPI (1.5 mol%), nBu4NF (3 equiv.) R1 PinY+B2Pin2- ► YR2 THF, r.t., 405 nm LED R2

[0136] Borylation was performed according to the following general procedure (GP-4). In a glovebox, a 5 mL glass vial containing a stirring bar was sequentiallycharged with BPI (7.5 pmol, 1.5 mol%) and nBiuNF (1.5 mmol, 1.5 mL, 3.0 equiv., 1.0M in THF). The mixture was stirred for 20 minutes at 23°C, and the color changed from orange to light green. Subsequently, the aryl fluorides (0.5 mmol) and B2Pin2 (2.5 equiv.) were added in one portion. The glass vial was placed into the photoreactor (405 nm LED) and stirred for corresponding time. The temperature was kept at approximately 23°C through cooling with six mini fans. After reaction, the crude mixture was purified by column chromatography on silica gel to afford the desired products. Highly volatile or lower boiling point C-F containing substrates (organofluorides) were added outside the glove box by using a syringe. Table 4-1 shows selected conversion products from borylation reactions of their corresponding C-F containing substrates, % yield (by GC), and reaction time. BPin refers to pinacolborane.Table 4-1

[0137] Overall, the results indicate that embodiments described herein enable borylation of various organofluorides, including electron-poor and electron-rich aryl fluorides. When reaction conditions that included a hydrogen source were attempted for borylation, a low yield of desired product was obtained with a substantial amount of the hydrodefluorination product identified. To overcome this undesired reactivity, the inventors found that omission of tert-AmylOH — which may serve as the primary source of hydrogen — improved conditions for cross-coupling. The absence of tert- AmylOH, meaning that there is no alcohol present to assist in F oxidation, may indicate that F oxidation in aprotic solvents occurs through p-acid interactions with Lewis basic anions. Through this modulation, a diverse array of fluorides were borylated to the corresponding products (S52 to S61) via radical coupling reaction with bis(pinacolato)diboron. The diborylation product S62 may also be obtained starting from 1,4-difluorobenzene. Notably, aryl boronates other than pinacol boronate are generated using the corresponding diboron esters (S63 and S64). Considering that borylation reagents are heavily used in drug and bioactive molecule syntheses, borylated derivatives of (-)-menthol (S65), geraniol (S66) and cholesterol (S67) may be generated in very good yields up to 60%. As described below, embodiments described herein also enable phosphonylation (S70 to S73), (hetero)arylation (S74 to S80), sulfuration (S81 to S85), and selenization (S86). Such products (S70 to S86) represent excellent potential starting materials or intermediates for target molecules.Example 4-2: Phosphonylation reaction. Scheme S4-2 shows an example reaction diagram for the phosphonylation reaction of aryl fluorides.Scheme S4-2 oR1F BPI (1.0-1 .5 mol%), nBu4NF (3 equiv.) R1-OEtY+p(OEt)3 - - Y 'bEtR2 THF / MeCN, r.t., 405 nm LED R2

[0138] Phosphonylation of aryl fluorides were performed according to the following general procedure (GP-5). In a glovebox, a 5 mL glass vial containing a stirring bar was sequentially charged with BPI (5.0 pmol, 1.0 mol%) and nBu4NF (1.5 mmol, 1.5 mL, 3.0 equiv., 1.0M in THF). The mixture was stirred for 20 minutes at 23°C, and the color changed from orange to light green. Subsequently, the aryl fluorides (0.5 mmol), triethylphosphite (P(OEt)s, 5.0 equiv.) and MeCN (1.0 mL) were added in one portion. The glass vial was placed into the photoreactor (405 nm LED) and stirred for corresponding time. The temperature was kept at approximately 23 °C through cooling with six mini fans. After reaction, the crude mixture was purified by column chromatography on silica gel to afford the desired products. Table 4-2 shows selected conversion products from phosphonylation reactions of their corresponding C-F containing substrates (organofluorides), % yield (by GC), and reaction time.Table 4-2Example 4-3: Arylation and Heteroarylation Reactions. Scheme S4-3 shows an example reaction diagram for arylation or heteroarylation of aryl fluorides.Scheme S4-3

[0139] Arylation and heteroarylation of aryl fluorides were performed according to the following general procedure (GP-6). In a glovebox, a 5 mL glass vial containing a stirring bar was sequentially charged with BPI (7.5 pmol, 1.5 mol%) and nBu4NF (1.5 mmol, 1.5 mL, 3.0 equiv., 1.0M in THF). The mixture was stirred for 20 minutes at 23°C, and the color changed from orange to light green. Subsequently, the organofluoride (e.g., an aryl fluoride, 0.5 mmol), an arene or heteroarene couplingpartner (20.0 equiv.) and DMSO (1.0 mL) were added in one portion. The glass vial was placed into the photoreactor (405 nm LED) and stirred for corresponding time. The temperature was kept at approximately 23°C through cooling with six mini fans. After reaction, the crude mixture was purified by column chromatography on silica gel to afford the desired products. Table 4-3 shows selected conversion products from arylation or heteroaryl ati on reactions of their corresponding C-F containing substrates (organofluorides), % yield (by GC), and reaction time. For conversion products S74 to578 the organofluoride was a fluorobenzene (with varying substituents) and the heteroarene coupling partner (reactant) was N-methylpyrrole. For conversion products579 and S80, the organofluoride was fluorobenzene and the heteroarene coupling partner (reactant) was 1 -phenylpyrrole or 1 -benzyl- IH-pyrrole.Table 4-3Example 4-4: Sulfuration and Selenization Reactions. Scheme S4-4 shows an example reaction diagram for the sulfuration and selenization reactions of aryl fluorides.Scheme S4-4R1F BPI (1 .5 mol%), nBu4NF (3 equiv.)I + A vn p l xA 2 _R2 THF, r.t., 405 nm LED

[0140] Sulfuration and selenization reactions of aryl fluorides were performed according to the following general procedure (GP-7). In a glovebox, a 5 mL glass vial containing a stirring bar was sequentially charged with BPI (7.5 pmol, 1.5 mol%) and nBu4NF (1.5 mmol, 1.5 mL, 3.0 equiv., 1.0M in THF). The mixture was stirred for 20 minutes at 23°C, and the color changed from orange to light green. Subsequently, the aryl fluorides (0.5 mmol) and coupling partner (3.0 equiv.) were added in one portion. The glass vial was placed into the photoreactor (405 nm LED) and stirred for corresponding time. The temperature was kept at approximately 23 °C through cooling with six mini fans. After reaction, the crude mixture was purified by columnchromatography on silica gel to afford the desired products. Table 4-4 shows selected conversion products for the sulfuration or selenization reactions of their corresponding C-F containing substrates (organofluorides), % yield (by GC), and reaction time. For conversion products S81 to S85 the organofluoride was a fluorobenzene (with varying substituents) and the coupling partner (reactant) was dimethyldisulfide (S2Me2). For conversion product S86, the organofluoride was fluorobenzene and the coupling partner (reactant) was dibutyl diselenide (Se2 / / Bu2).Table 4-4Example 5: Proposed Mechanism

[0141] To evaluate the mechanistic hypothesis shown in FIG. 2, the inventors used a more symmetric variant, BPI-N, which mimics BPI while replacing core- substituents. BPI-N refers to BPI where the three Ar groups (Ar = -OMePh) are replaced with hydrogen atoms. With BPI-N, the inventors isolated the intermediate formed upon dark reaction with nBu4NF. Characterization by1H-,13C-, and 2D-NMR, and UV-vis spectroscopy supported formation of the ring-opened compound (BPI-N-RO) possessing amide and carboxylate groups.19F-NMR of the isolated product indicated that neither a covalent fluoride adduct nor a fluoro-Meisenheimer were formed. Density functional theory (DFT) studies suggested that hydroxide (OFF), generated through F reacting with water, may hydrolyze the imide ring leading to the formation of the ring- opened BPI-N-RO in an overall process that is exergonic by -14.0 kcal / mol. NMR experiments with the -OMePh substituted BPI supported the same reactivity with nBu4NF leading to formation of BPI-RO. BPI-RO is stable in solution and its emission spectrum exhibited a hypsochromic shift relative to BPI (kmax= 565 nm [BPI], 483 nm [BPI-RO], This observation is in contrast to anion-7t formation which typically resultsin a bathochromic shift. The water content in nBmNF was found to significantly impact the catalyst’s performance. While trace amounts of water are used for the imide hydrolysis and BPI-RO formation, a large amount of water may lead to passivation of F ions as HF2 , diminishing its efficacy as an electron donor. Other common F sources did not show evidence for BPI-RO formation, which may be due to insolubility in the reaction conditions. Upon irradiating BPI-RO with excess nB^NF in the absence of an alcohol with a 405 nm LED, a new species was observed that is electron paramagnetic resonance (EPR) active with accompanying changes in the UV-vis spectra. The EPR spectra was assigned to BPI-RO' . Based on the Eo.o value of 2.78 eV and E1 / 2 of -1.84 V vs SCE (corresponding to BPI-RO + e" BPI-RO' ) the potential of BPI-RO* acting as an oxidant (BPI-RO * / BPI-RO' ) was estimated to be 0.94 V vs SCE. SCE refers to saturated calomel electrode. DFT calculations suggest this potential is not sufficient to drive F oxidation (requiring a potential of +2.34 V vs SCE). However, this potential is modified when F is hydrogen bonded with alcohols. Computations suggested that clusters comprised of tert-AmylOH bound F may be oxidized at 0.76 V vs SCE and may be thought of as F assisting in the oxidation of the corresponding alkoxide. When the experiment was performed in the presence of a proton source (tert-AmylOH), BPI- RO’" may be rapidly transformed through irradiation with visible light. A new structured emission band that peaks at +max = 450 nm was observed to form and no radical anion was detected. The new species was air-stable and photoluminescent with a lifetime on the order of 10 ns. The inventors believe this compound to be the closed- shell singlet species BPI-RO-H that is not in a doublet state. Computed thermochemistry and reduction potential values indicated that BPI-RO-H may be an intermediate with a new C-H bond adjacent to the carbonyl group via protonation; the redox potential of the excited state BPI-RO-H * up to -3.64 V vs. SCE. Indeed, 'H- NMR experiments supported the formation of an air stable intermediate, while photoluminescence quenching of this species was observed with aryl fluorides, such as methyl 4-fluorobenzoate and fluorobenzene, demonstrating the high reducing strength. In support of the closed-shell mechanism involving an overall multi-photon excitation process, a near quadratic dependency of the conversion of fluorobenzene to the irradiation density was observed. Deuterium-labeling experiments were performed to determine the source of the hydrogen in the dehalogenated product, showing participation may be by THF, nBu4NF, and added alcohol.

[0142] Embodiments of the present disclosure generally relate to processes for activation of carbon-fluorine (C-F) bonds using an organic photoredox catalyst. Embodiments described herein also relate to processes for converting a substrate comprising a C-F bond (an organofluoride) to a conversion product such as a reduction product or a cross-coupling product. Overall, the inventors have found an organic photocatalytic system capable of activating challenging C-F bonds in a wide range of mono- and poly-fluorinated organofluorides (such as mono- and poly-fluorinated aryl and alkyl substrates) for the purposes of both hydrodefluorination and generation of precursors for cross-coupling reactions. The efficacy of this photocatalyst has been showcased through, for example, its ability to degrade PFAS compounds and fluorinated polymers. Given the mild nature and operational simplicity of the reaction setup enabled by embodiments of the present disclosure, embodiments described herein facilitate the utilization of readily available organofluorides in chemical synthesis and provide a novel approach for breaking down persistent fluorinated compounds.

[0143] As used herein, reference to chemical compound without specifying a particular isomer (such as butanol) expressly discloses all isomers (such as n-butanol, iso-butanol, sec-butanol, and tert-butanol). For example, reference to a chemical compound having 4 carbon atoms expressly discloses all isomers thereof. When a compound is described herein such that a particular isomer, enantiomer, or diastereomer of the compound is not specified, for example, in a formula or in a chemical name, that description is intended to include each isomer, diastereomer, and enantiomer of the compound described individually or in any combination.

[0144] As is apparent from the foregoing general description and the specific embodiments, while forms of the embodiments have been illustrated and described, various modifications may be made without departing from the spirit and scope of the present disclosure. Accordingly, it is not intended that the present disclosure be limited thereby. Likewise, the term “comprising” is considered synonymous with the term “including.” Likewise whenever a composition, an element or a group of elements is preceded with the transitional phrase “comprising,” it is understood that we also contemplate the same composition or group of elements with transitional phrases “consisting essentially of,” “consisting of,” “selected from the group of consisting of,” or “Is” preceding the recitation of the composition, element, or elements and vice versa, such as the terms “comprising,” “consisting essentially of,” “consisting of’ also include the product of the combinations of elements listed after the term.

[0145] For purposes of this present disclosure, and unless otherwise specified, all numerical values within the detailed description and the claims herein are modified by “about” or “approximately” the indicated value, and consider experimental error and variations that would be expected by a person having ordinary skill in the art. For the sake of brevity, only certain ranges are explicitly disclosed herein. However, ranges from any lower limit may be combined with any upper limit to recite a range not explicitly recited, as well as, ranges from any lower limit may be combined with any other lower limit to recite a range not explicitly recited, in the same way, ranges from any upper limit may be combined with any other upper limit to recite a range not explicitly recited. For example, the recitation of the numerical range 1 to 5 includes the subranges 1 to 4, 1.5 to 4.5, 1 to 2, among other subranges. As another example, the recitation of the numerical ranges 1 to 5, such as 2 to 4, includes the subranges 1 to 4 and 2 to 5, among other subranges. Additionally, within a range includes every point or individual value between its end points even though not explicitly recited. For example, the recitation of the numerical range 1 to 5 includes the numbers 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, among other numbers. Thus, every point or individual value may serve as its own lower or upper limit combined with any other point or individual value or any other lower or upper limit, to recite a range not explicitly recited.

[0146] As used herein, the indefinite article “a” or “an” shall mean “at least one” unless specified to the contrary or the context clearly indicates otherwise. For example, embodiments comprising “a solvent” includes embodiments comprising one, two, or more solvents, unless specified to the contrary or the context clearly indicates only one solvent is included.

[0147] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

CLAIMSWhat is claimed is:

1. A process for converting an organofluoride to a conversion product, comprising: forming a reaction mixture comprising an organofluoride, an organic catalyst, a co-catalyst, a hydrogen source, and an optional solvent, the organofluoride represented by formula (I):R1F k (I), wherein: each of R1and R2of formula (I) are, independently, hydrogen, unsubstituted hydrocarbyl, substituted hydrocarbyl, or a functional group comprising at least one element from Group 13-17 of the periodic table of the elements; and at least one of R1or R2of formula (I) is the unsubstituted hydrocarbyl, the substituted hydrocarbyl, or the functional group comprising at least one element from Group 13-17; and exposing the reaction mixture to light to convert the organofluoride, under conversion conditions, to a conversion product represented by formula (II):R1HR2(II)2. The process of claim 1, wherein the organic catalyst is metal free and comprises a benzo[ghi]perylene moiety represented by formula (VII):

3. The process of claim 1, wherein the organic catalyst is metal free and comprises a benzo[ghi]perylene moiety represented by formula (VII- A)wherein the wavy bonds of formula (VII-A) represent connections to an unsubstituted hydrocarbyl, a substituted hydrocarbyl, or a functional group comprising at least one element from Group 13-17.

4. The process of claim 1, wherein: the co-catalyst comprises nBu4NF, Et4Nf, Me4NF, Me4N0H, or combinations thereof; the hydrogen source comprises an alcohol; the optional solvent comprises tetrahydrofuran, dimethylformamide, dichloromethane, toluene, dimethylacetamide, acetonitrile, dimethyl sulfoxide, or combinations thereof; or combinations thereof.

5. The process of claim 1, wherein at least one of R1or R2of formula (I) is an unsubstituted hydrocarbyl having 1 to 20 carbon atoms or a substituted hydrocarbyl having 1 to 20 carbon atoms.

6. The process of claim 1, wherein the conversion conditions comprises a temperature that is about 100°C or less.

7. The process of claim 1, wherein the light has a wavelength that is from about 300 nm to about 800 nm, or from about 350 nm to about 450 nm.

8. A process for converting a PF AS compound to a conversion product, comprising: forming a reaction mixture comprising a PF AS compound, a metal-free organic catalyst, a co-catalyst, a hydrogen source, and an optional solvent, the PFAS compound represented by formula (III):wherein: each of R3and R4of formula (III) are, independently, hydrogen, unsubstituted hydrocarbyl, substituted hydrocarbyl, or a functional group comprising at least one element from Group 13-17 of the periodic table of the elements; and at least one of R3or R4of formula (III) is the unsubstituted hydrocarbyl, the substituted hydrocarbyl, or the functional group comprising at least one element from Group 13-17; and exposing the reaction mixture to light to convert the PF AS compound to a conversion product represented by formula (IV):

9. The process of claim 8, wherein at least one of R3or R4of formula (III) is an unsubstituted hydrocarbyl having 1 to 20 carbon atoms or a substituted hydrocarbyl having 1 to 20 carbon atoms.

10. The process of claim 8, wherein at least one of R3or R4of formula (III) is a substituted hydrocarbyl comprising 1 to 20 carbons and a hydroxyl (-OH) group.

11. The process of claim 8, wherein at least one of R3or R4of formula (III) is a substituted hydrocarbyl comprising 1 to 3 carbons and a hydroxyl (-OH) group.

12. The process of claim 8, wherein at least one of R3or R4of formula (III) comprises an ester represented by formula (V-A):O+fi-°R5(V-A), wherein:R5of formula (V-A) is an unsubstituted hydrocarbyl comprising 1 to 6 carbon atoms; the wavy bond (f^) of formula (V-A) represents a connection to the -CF2- group of the PF AS compound of formula (III); andthe wavy bond ( ^ ) of formula (V-A) represents a connection to the methylene (-CH2-) group of the conversion product of formula (IV).

13. The process of claim 8, wherein at least one of R3or R4of formula (III) comprises a substituted aryl or an unsubstituted aryl.

14. The process of claim 8, wherein at least one of R3or R4of formula (III) comprises a carboxylic acid represented by formula (V-B):wherein the wavy bondof formula (V-B) represents a connection to the -CF2- group of the PF AS compound of formula (III).

15. The process of claim 14, wherein the carboxylic acid is converted to an ester by the process.

16. A process for converting an organofluoride to a conversion product, comprising: forming a reaction mixture comprising an organofluoride, a metal-free organic catalyst, a co-catalyst, a coupling partner comprising at least one element from Group 13-16 of the periodic table of the elements, and an optional solvent, the organofluoride represented by formula (I):wherein: each of R1and R2of formula (I) are, independently, hydrogen, unsubstituted hydrocarbyl, substituted hydrocarbyl, or a functional group comprising at least one element from Group 13-17; and at least one of R1or R2of formula (I) is the unsubstituted hydrocarbyl, the substituted hydrocarbyl, or the functional group comprising at least one element from Group 13-17; and exposing the reaction mixture to light to convert the organofluoride to a conversion product represented by formula (VI):wherein A" of formula (VI) comprises the at least one element from Group 13-16.

17. The process of claim 16, wherein the conversion product of formula (VI) is represented by formula (VI- A), formula (VI-B), or formula (VI-C):

18. The process of claim 16, wherein the conversion product of formula (VI) is represented by formula (VI-D):

19. The process of claim 16, wherein the conversion product of formula (VI) is represented by formula (VI-E):wherein:Z" of formula (VI-E) is aryl, optionally substituted by one or more substituents comprising an unsubstituted hydrocarbyl, a substituted hydrocarbyl, or a functional group comprising at least one element from Groups 13-17; orZ" of formula (VI-E) is heteroaryl, optionally substituted by one or more substituents comprising an unsubstituted hydrocarbyl, a substituted hydrocarbyl, or a functional group comprising at least one element from Groups 13-17.

20. The process of claim 16, wherein the conversion product of formula (VI) is represented by formula (VI-F):wherein: X of formula (VI-F) is S or Se; and RAof formula (VI-F) is an unsubstituted hydrocarbyl or a substituted hydrocarbyl.

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