41 results about "Bond cleavage" patented technology

The present application relates to the technical field of organic synthesis, and particularly relates to a method for preparing (+)-crispine A by means of biological enzyme resolution. First, 6,7-dimethoxy-3,4-dihydroisoquinoline-2-oxide is subjected to 1,3-dipolar cycloaddition with allyl alcohol to obtain a first compound; then the first compound is added into a sulfonylation reagent and zinc powder to obtain a racemate second compound through a three-step continuous series reaction of primary alcohol sulfonylation, nitrogen-oxygen bond cleavage and ring formation; then the second compound is mixed with vinyl acetate and biological enzyme, and chiral resolution is carried out under the action of the biological enzyme to obtain a third compound with right-handed optical rotation and a fourth compound with left-handed optical rotation; finally, the third compound is mixed with an alkaline reagent and a sulfonylation reagent, and then secondary alcohol sulfonylation is carried out to obtain a fifth compound with right-handed optical rotation; the fifth compound is mixed with a deoxidizing reagent to carry out deoxidation reaction, and (+)-crispine A is prepared. The method is simple, green and environmentally friendly, and can be produced in large quantities.

The divisional application provides a method for breaking and forming a tetravalent uranium photocatalytic carbon-carbon bond, which comprises the following steps: dissolving a tetravalent uranium catalyst with a molecular formula of L-U (NO3) 3 (OMe) in an organic solvent in an environment of-40 DEG C to 80 DEG C under the conditions of inert gas and blue light with a light source of 440-450 nm; and then adding olefin with a chemical structural formula shown in the specification and cyclic alcohol with a chemical structural formula shown in the specification for reaction to obtain a product. According to the forming method, tetravalent uranium serves as a photocatalyst, olefin which is almost not reacted originally reacts with cyclic alcohol with ring tension, the conversion rate of the reaction is increased, the conversion rate can reach 99% at most, and the excellent yield and the high atom economy are achieved.

A method and apparatus for monitoring and / or controlling the extent of denaturation and / or bond cleavages of proteins on any surface (e.g., biological tissues, biofilms, etc.). In one embodiment, a low power laser (e.g., a 5 mW, 362 nm diode laser) is directed through a biological sample to a photodetector. The sample is heated by a set of radiant heaters to between about 220° C. and about 250° C. in a time period of between 10 seconds to 60 seconds. The baseline transmissivity of the sample is monitored continuously throughout treatment of the biological sample via continuous monitoring of the signal voltage detected at the photodetector. Upon detection of increase in relative transmissivity in the biological sample, the heating treatment is concluded and the biological sample is removed for in situ protein identification as part of an imaging MALDI-MS measurement.

This invention discloses a visible light-induced method for synthesizing α,β-unsaturated acetylide amides, belonging to the field of organic synthesis. The invention constructs a visible light-responsive aromatization-driven carbamoyl radical precursor—a dihydroquinazolinone derivative precursor containing a carbamoyl segment. Under direct visible light irradiation, a single-electron process is triggered, leading to C-C bond cleavage and aromatization, thereby efficiently releasing a carbamoyl radical in situ. Subsequently, this radical undergoes selective acetylation transfer and coupling with an acetylation-based high-valent iodine reagent, achieving the rapid construction of the target α,β-unsaturated acetylide amide. This process can be completed via a one-pot pathway of "visible light direct-driven—radical generation—acetylation transfer / coupling," avoiding the introduction of additional photocatalysts, making the reaction system simpler, the cost more controllable, and the post-processing more convenient.

This invention relates to a method for preparing deuterated compounds, using peroxides (such as D₂O₂) as the key deuterium source, which provides the deuterium atoms required for the reaction. When the peroxide comes into contact with the target compound and under the action of a selected catalyst, the energy of ultraviolet light can excite the reaction system, causing the OD bonds in the peroxide to break and releasing active deuterium atoms. These active deuterium atoms can then exchange with hydrogen atoms in the target compound, completing a hydrogen-deuterium substitution. The advantage of this method is that it can be operated under relatively mild conditions—that is, without the need for extreme temperature or pressure conditions—while still achieving high deuteration rates and yields. This means that this method may be more economically feasible on an industrial scale, reducing energy consumption and the generation of byproducts.

The application provides a preparation method of an electrocatalytic SCF-substituted dihydrofuran compound, and belongs to the technical field of compound preparation. The application uses diazonium and ethylene compounds as substrates, uses an SCF source as a sulfur-containing and fluorine-containing fragment donor, realizes a one-pot cascade reaction of ring formation through electrolysis, and thus constructs the SCF-substituted dihydrofuran compound. The raw material of the application has a wide source, uses electric current as a reaction driving force, avoids or reduces the use of additional photosensitizers and chemical oxidation-reduction reagents, and has the one-pot cascade characteristics of ring C-N bond breaking, C-O bond construction, trifluoromethylation and ring formation and the like, so that the step economy can be improved.

Gold(I) complexes capable of absorbing light in the near-UV and / or visible region, and methods of making and using the same, are described. These gold(I) complexes have photochemical reactivity, such as strong absorption of near-UV and / or visible light, quenching rate constants of > 3.5 x 10 5 s ‑1 This enables them to catalyze photoredox reactions under near-UV and / or visible light, such as homocoupling of organic halides (e.g., alkyl halides and aryl halides), alkylation of 2-phenyl-1,2,3,4-tetrahydroisoquinolines, cyclization of indoles, reductive dehalogenation of aryl halides, and / or C-H bond cleavage, among others. The yields of products of photo-induced organic reactions catalyzed by the gold(I) complexes described herein can be higher than the yields of the same products formed from the same reactions under the same reaction conditions using [Au2(μ-dppm)2](Cl)2, [Ru(bpy)3](Cl)2, and / or [fac-Ir(ppy)3] at the same or higher loading than the loading of the one or more gold(I) complexes.

The present disclosure relates in some aspects to methods, systems, and kits for using diphosphonic acid to promote N—O bond cleavage in a 3′ O—NH2 nucleotide in a cell or tissue sample. In some aspects, diphosphonic acid is used to promote N—O bond cleavage in a 3′ O—NH2 blocked reversible terminator during multiple cycles of a nucleic acid sequencing reaction in a cell or tissue sample. In some embodiments, the chemical reaction of the 3′ O—NH2 blocked reversible terminator with diphosphonic acid releases free alcohols and phosphoric acid derivatives, which are not damaging to the cell or tissue sample.

Crumb rubber obtained from recycled tires is subjected to a process involving photodissociation to break a sulfur bond, sulfur-sulfur and / or sulfur-carbon bonds. The process utilizes a component that generates photonic energy upon being subjected to a compressing force (e.g., pressure). The photonic energy is bandwidth resonant with the sulfur-sulfur and / or sulfur-carbon bond, causing the bond to break apart. The resulting rubber is suitable for use in applications typically utilizing virgin rubber, such as new tires, engineered rubber articles, and asphalt rubber for use in waterproofing and paving applications.

The invention belongs to the technical field of organic synthesis, and particularly relates to an alkyl aminophenol compound and a synthesis method thereof. Aiming at the problems of harsh conditions, insufficient selectivity and the like of the existing arylamine C-N bond breaking method, the invention provides a novel method for synthesizing the p-alkyl aminophenol compound by oxidizing aromatic amine through PhI (OAc) 2 to selectively break a C (aryl)-N bond under a mild condition. According to the method, a series of p-alkyl aminophenol compounds with potential biological activity can be synthesized within 3 hours at the yield of 56-82%, and the method is suitable for preparation of derivatives such as indole ethylaminophenol and adamantane methylaminophenol.

The present invention belongs to the field of pharmaceutical chemistry and related chemical technologies, and discloses a method for preparing trifluoromethyl ketone compounds based on palladium-catalyzed C-N bond cleavage. The method uses arylboronic acid as a raw material and trifluoroacetamide compounds as a trifluoroacetylating agent, and prepares trifluoromethyl ketone compounds under the catalytic action of palladium, thereby achieving its green and efficient synthesis. The method has the advantages of easy preparation and storage of trifluoroacetylating agents, high reaction selectivity, good functional group compatibility, wide substrate application range, and environmental friendliness. Since trifluoromethyl ketone compounds are an important functional molecular skeleton structure, they are widely used in the fields of fine chemicals and pharmacy; therefore, the present invention has great application value and social and economic benefits.

The present invention relates to the technical field of fine chemical engineering, and discloses a method for preparing 2,2-dibromoacetophenone by C-S bond cleavage. The specific steps are as follows: Using 1-phenylethyl methyl sulfide as the reaction raw material, dichlorodimethylhydantoin and water as important additives, heating and reacting in an organic solvent to obtain the target product 2,2-dibromoacetophenone. This method has the advantages of simple operation, avoiding the use of additional catalysts and the use of highly toxic and corrosive liquid bromine, and has potential application value.

The invention discloses a method for activating an aryl chloride C (sp2)-Cl bond to generate an aryl phenol compound, which is characterized in that a visible light excitation photosensitizer is utilized for catalysis, and in a reaction solvent, a raw material in a formula (1) realizes C (sp2)-Cl bond breakage to generate the aryl phenol compound in a formula (3) under the auxiliary catalysis condition of acid. Under the conditions of room temperature and normal pressure, water is used as an oxygen source, so that the method is green and environment-friendly, the reaction operation is simple, the substrate universality is wide, the functional group tolerance is good, and the reaction yield is high; the reaction not only can realize simple aryl chloride conversion, but also can realize conversion of various amino acid derivatives and drug molecules such as phenylalanine derivatives, ketoprofen derivatives, biphenyl derivatives, bupropion, clofibrate, pyrimethamine and the like to generate corresponding aryl phenol compounds; and compared with the common tubular reaction, the fluid amplification efficiency is improved by nearly hundreds of times. The invention provides a new thought and method for synthesis of the aryl phenol compound, and has a wide application prospect.

This invention belongs to the field of industrial catalysis and bioenergy conversion technology, and relates to a method for selectively cleaving C-C bonds in lignin to prepare alkanes using a Ni-Co spinel catalyst and its applications. The method of selectively cleaving C-C bonds in lignin using a Ni-Co spinel catalyst can achieve efficient C-C bond cleavage under mild conditions (250~290°C, 2-4 MPa) and a hydrogen atmosphere, without the need for excessively high temperatures and pressures. It exhibits good cleavage activity for various C-C bond types in lignin (such as α-1, 5-5′, β-1, β-β′, etc.), showing broad substrate applicability. When used to prepare cycloalkanes from o-benzylphenol, the catalytic conversion rate can reach over 99%, and the cycloalkane yield can reach over 70%. The cycloalkane yield from the catalytic cleavage of real lignin ranges from 7% to 25%. The method of this invention does not require the use of precious metals and has low cost.

The invention discloses a seven-membered silicon heterocyclic compound and a preparation method and application thereof.The structural formula of the seven-membered silicon heterocyclic compound is shown as (I) or (II), and the preparation method of the seven-membered silicon heterocyclic compound is as follows: in the presence of a ligand, a palladium catalyst and a reaction medium, an allenyl functionalized silicon hybrid quaternary compound is subjected to intramolecular selective cycloaddition through silicon-carbon bond breakage, and the seven-membered silicon heterocyclic compound is obtained; the compound provided by the invention can be applied to preparation of silicon-containing chiral drugs as an intermediate for drug synthesis. In the product range, richer and more complex functional groups can be introduced, the product range is widened to a great extent, and a foundation is laid for subsequent application and transformation. # imgabs0 #

The application discloses a multifunctional backbone molecule for controllable and visual monitoring of drug release and a preparation method and application thereof, the multifunctional backbone molecule has a structure shown in formula I, includes a tetrazine structural unit and a phenanthrene dioxin skeleton, and fluorescence of the phenanthrene dioxin is quenched through fluorescence resonance energy transfer effect between the tetrazine and the phenanthrene dioxin parent nucleus. The multifunctional backbone molecule provided by the application can be subjected to a reverse electron demand Diels-Alder bioorthogonal bond cleavage reaction with a prodrug modified by a trans-cyclooctene, 3-isocyanopropyl or 3-isocyanopropyl-1-carbamoyl group, so that the quenching effect is destroyed, fluorescence is recovered, the prodrug is activated, controllable release and visual monitoring of the drug are realized. In addition, the multifunctional backbone molecule provided by the application can be connected with a targeting group on the phenanthrene dioxin skeleton, so that controllable release of the drug at a target site and real-time visual monitoring of the drug release are realized.

The invention discloses a preparation method of a covalent organic framework TFP-DAAQ and application of the covalent organic framework TFP-DAAQ in catalysis of cracking of C-C bonds in lignin. The catalyst is utilized to efficiently catalyze and convert the lignin model compound under a mild condition to obtain the aromatic compound, the preparation method is environment-friendly, the reaction condition is mild, noble metal is not needed, the heterogeneous phase is realized, the separation process is simple, the cost is lower, and fewer by-products are generated. The conversion rate of the typical beta-O-4 model compound 2-phenoxy-1-phenyl-ethanol reaches 85.6-97.0%, the selectivity of the main product benzaldehyde can reach 66.2%-69.1%, the product is easy to separate, and the method has a good industrial production cost advantage.

The invention discloses a light response type self-adaptive interface bridging agent, a preparation method thereof and application of the light response type self-adaptive interface bridging agent in mixed plastic recovery, and belongs to the technical field of high polymer material recovery. The interface bridging agent is symmetrical in molecular structure, the two ends of the interface bridging agent are 3-(trifluoromethyl)-3H-diaziridine bridging end groups capable of generating carbene, and the middle part of the interface bridging agent comprises an azobenzene photosensitive driving unit and a self-adaptive connecting unit (such as a disulfide bond). The core of the method is that illumination with different wavelengths is utilized: under ultraviolet irradiation, azobenzene is isomerized into cis-conformation, internal stress is generated to promote bond breakage of a connecting unit, and self-adaptive network dissociation is realized; under the irradiation of visible light, the azobenzene recovers trans-conformation, and the connection unit bonds are recombined to realize network reconstruction. When the mixed plastic is recycled, the interface bridging agent can reinforce interface bonding through a carbene insertion reaction to form a'molecular rivet ', and dissociation and reshaping of the material are realized through light-operated reversible regulation and control. According to the invention, remote, reversible and accurate regulation and control of the material performance are realized, the process is mild, the recovery efficiency of the incompatible mixed plastic and the performance of the regenerated product are obviously improved, and the method has a good application prospect.

The application discloses a kind of trinuclear tin complex, its preparation method and application in extreme ultraviolet lithography and electron beam lithography.The trinuclear tin complex has the following general formula I structure;It is prepared by the reaction of tin core with R1 substituent group modification and isophthalic acid with R2 substituent group modification according to the molar ratio of 1:1-2 in solvent;The trinuclear tin complex disclosed in the application connects different ligands, enhances the thermal chemical stability of the whole trinuclear tin complex, improves the EUV absorption rate, the molecular size is small, the composition is single, the Sn-C bond is broken during exposure to initiate high efficient solubility transformation, the sensitivity is far more than similar products, especially in electron beam lithography, performance revolution is improved.

This invention discloses a photocatalyst, its preparation method, and its application. The photocatalyst is a modified catalyst POSS-PDI formed by combining CPDI (3,4,9,10-perylenetetracarboxylic dianhydride) and cage-like groups POSS-NH2 (aminopropylheptyl-cage polysilsesquioxane). The mass ratio of CPDI to POSS-NH2 in the modified catalyst POSS-PDI is 1:3.29. The mass ratio of g-CN (mesoporous graphitic carbon nitride nanosheets) to POSS-PDI in the g-CN / P-PDI type II photocatalyst is 3wt%. The preparation method of this invention is simple. By constructing a heterojunction, the prepared type II photocatalyst exhibits excellent catalytic activity and stability. Under the synergistic effect of light irradiation and multiple reaction conditions, the depolymerization of the lignin model compound β-O-4 in acetonitrile can reach 99%, and the C-C bond cleavage selectivity reaches 96%.

The present application relates to the technical field of stereoselective monofluoroolefination of indolines at C7 position, in particular to a method for stereoselective C-H bond monofluoroolefination of indolines at C7 position catalyzed by ruthenium, comprising the following steps: under the action of a ruthenium catalyst and a base, carrying out C-H bond monofluoroolefination reaction of indolines represented by formula (I) with gem-difluoroalkenes represented by formula (II) or 3-(2,2-difluorovinyl)thiophene or 4-(2,2-difluorovinyl)benzo[d][1,3]dioxole to prepare compounds represented by formula (III). The present application uses inexpensive ruthenium catalyst, and through C-H bond activation / C-F bond cleavage, a series of Z-type alpha-monofluoroolefination pyridine indolines are obtained, and the method has strong site and stereoselectivity, is efficient and low in cost. In addition, the target compounds obtained by synthesis have certain antibacterial activity, and can provide a basis for the development of such lead compounds.

The present application belongs to the technical field of organic synthesis, and particularly relates to an addition product of an alkyl radical and a capture agent, and its addition method and application. A secondary alkyl ethylbenzene A, a capture agent B, an acridinium salt photocatalyst, and an additive are dissolved in an organic solvent and subjected to a light-irradiation reaction to obtain an addition product of the alkyl radical and the capture agent; wherein the secondary alkyl ethylbenzene A has the general structural formula: #imgabs0# Formula I; the capture agent B is selected from at least one of #imgabs1##imgabs2#TsCN; and the structural formula of the addition product of the alkyl radical and the capture agent includes at least one of #imgabs3#. A method is proposed for inducing carbon-carbon bond cleavage in secondary alkyl ethylbenzene by single-electron transfer oxidation, which reacts with a capture agent to generate a product. The reactant raw materials are easily accessible, the reaction process is safe and controllable, the operation is simple, and the production cost is low. The addition product has high functionality and more diverse applications.

The invention relates to the use of a monomer according to formula (1) for producing a bond break in a polymer that is obtained from at least one monomer according to formula (1), wherein the bond break is induced by applying an electrical voltage across the polymer, and to a method for the electrochemical disintegration of such a polymer. The invention further relates to polymerisable monomers according to formula (1) and polymers obtained therefrom.

The invention discloses a method for synthesizing a benzyl alkyl ketone compound through visible light catalysis. The method for synthesizing the benzyl alkyl ketone compound through visible light catalysis comprises the following steps: in an inert atmosphere, adding an olefin compound, an anhydride compound or an acyl imidazole compound and a tertiary amine compound into an organic solvent of a photocatalyst, mixing, and carrying out a photoreaction under a visible light irradiation condition to obtain the benzyl alkyl ketone compound. According to the method, tertiary amine is oxidized into alpha-site free radical species of nitrogen under the mild photooxidation condition, so that fracture of olefin carbon-carbon pi bonds is induced, meanwhile, anhydride (or an acylimidazole compound) is used as an acyl source, fracture of carbon-carbon sigma bonds is promoted by using a visible light catalyzed oxidation-reduction strategy, and the olefin is synthesized. Therefore, the process of obtaining the benzyl alkyl ketone compound through the carbon-carbon bond breakage acylation reaction of olefin is realized. The synthesis method is mild, efficient and simple to operate, and has atom economy.

The application discloses a preparation method of an acousto-optic catalyst for catalyzing the cleavage of ether bonds in lignin, and belongs to the technical field of photocatalytic materials. 2+ The intercalation method is used for in-situ synthesis of ZnO in the layer spacing of MoS2, MoS2 / ZnO heterojunction catalyst is constructed, and the catalyst has strong piezoelectric response capability. The problems of traditional photocatalysts, such as fast recombination of photo-generated carriers and low mechanical energy utilization rate, are solved, and the shortcoming of the reduction of catalytic energy level after the construction of the heterojunction is also solved. Under the acousto-optic combined action, a large number of beta-O-4 bonds are broken, and high product selectivity is simultaneously achieved. The method is simple in operation and has significant technical advantages.

The present invention discloses a Cu-ZnO@Al2O3 catalyst, its preparation method, and application, belonging to the technical field of catalyst preparation. The present invention utilizes a coprecipitation method and a calcination reduction method to prepare the Cu-ZnO@Al2O3 catalyst. Based on Cu as the active component, Zn and Al oxides are introduced to enable the Cu-ZnO@Al2O3 catalyst to exhibit a relatively large number of L-acid sites, thereby promoting C-O bond cleavage during the electrocatalytic hydrogenation of furfural. Ultimately, relatively excellent catalytic performance is achieved for the highly selective electroreduction of furfural to 2-methylfuran. At a constant voltage reaction of 0.5 V vs. SHE for 1 hour, the selectivity for 2-methylfuran is 95%. This also avoids the rapid deactivation and steep current drop problems associated with elemental Cu as a cathode electrode material.

The application provides a preparation method for synthesizing aryl silicon compounds by iron catalysis of aryl ether carbon-oxygen bond cleavage and chlorosilane reaction, and solves the technical problems that the existing aryl silicon compound preparation method is not environmentally friendly and lacks stable carbon electrophiles. The application is specifically as follows: under an inert atmosphere, aryl ether, chlorosilane and an iron catalyst are added into an organic solvent, a Grignard reagent is dropped, stirring is carried out at room temperature, and after the reaction is completed, quenching is carried out, and aryl silicon compounds are obtained through separation and purification.

Provided is a method for depositing a film comprising a transition metal chalcogenide, the method comprising the steps of: injecting a transition metal precursor and a chalcogen precursor into a chamber; and reacting the transition metal precursor with the chalcogen precursor to deposit a film comprising a transition metal chalcogenide on a substrate, wherein the chalcogen precursor comprises a chalcogen-to-chalcogen bond, and a bond decomposition energy of the chalcogen-to-chalcogen bond is 275 kJ / mol or less.

A method and apparatus for monitoring and / or controlling the extent of denaturation and / or bond cleavages of proteins on any surface (e.g., biological tissues, biofilms, etc.). In one embodiment, a low power laser (e.g., a 5 mW, 362 nm diode laser) is directed through a biological sample to a photodetector. The sample is heated by a set of radiant heaters to between about 220° C. and about 250° C. in a time period of between 10 seconds to 60 seconds. The baseline transmissivity of the sample is monitored continuously throughout treatment of the biological sample via continuous monitoring of the signal voltage detected at the photodetector. Upon detection of increase in relative transmissivity in the biological sample, the heating treatment is concluded and the biological sample is removed for in situ protein identification as part of an imaging MALDI-MS measurement.

The invention discloses an Off-On type fluorescent probe compound, the chemical name of the Off-On type fluorescent probe compound is thiocarbonic acid O-(2-butyl-1, 3-dioxo-2, 3-dihydro-1H-benzo [de] isoquinoline-6-yl) O-(4-fluorophenyl) ester (short for 2B6NI-4FP-TC), a preparation method of the Off-On type fluorescent probe compound and application of the Off-On type fluorescent probe compound to detection of mercury ions in complex matrix samples such as ashing soil and tea leaves. During detection, Hg < 2 + > is combined with sulfur atoms of thiocarbonate and catalyzes ester bond breakage, 4-OH of a fluorescent parent nucleus is exposed, and a system fluorescent signal is remarkably amplified. The probe has extremely high selectivity and sensitivity, the detection limit is as low as 1.5 * 10 <-8 > M, the stability in a wide pH range is good, qualitative and quantitative detection of Hg < 2 + > can be realized through visual colorimetry and fluorescence spectrum, and the probe is particularly suitable for rapid and high-throughput detection of trace Hg < 2 + > in complex matrix samples such as traditional Chinese medicines and tea leaves subjected to ashing treatment.