A visible light-promoted method for the hydrodehalogenation of halogenated alkanes

Abstract

The present invention provides a method for the hydrodehalogenation of halogenated alkanes promoted by visible light, and belongs to the technical field of organic synthesis. The present invention carries out the hydrodehalogenation of halogenated alkanes under the condition of visible light illumination, and initiates free radicals under the promotion of visible light to realize the cleavage of the carbon-halogen bond of the halogenated alkanes to generate alkyl free radicals, and simultaneously utilizes mercaptan to provide a hydrogen source to generate a reduction hydrogenation product, and the addition of an organic amine is conducive to the capture of the halogen free radicals generated by the reaction, thereby improving the reaction rate and having a high yield. The method of the present invention is simple to operate, and the reaction conditions are mild, and the reaction can occur at room temperature. The hydrogen source is mercaptan, and has good tolerance to reducible functional groups such as carbon-carbon double bonds, ester groups, and cyano groups, and therefore has good functional group tolerance and a wide range of substrates.

Description

Technical Field

[0001] The invention relates to the technical field of organic synthesis, and in particular to a visible light-promoted method for hydrogenation and dehalogenation of halogenated alkane. Background Art

[0002] Halogenated organics are widely used in various fields such as agriculture, industry and life. They are discharged into the environment in large quantities during production, transportation and use, posing a potential threat to the health of animals and plants. Dehalogenation can effectively promote the degradation of halogenated organics and reduce the harm of organic halides to humans and the environment. This process can be achieved through metal-halogen exchange or metal (such as zinc)-mediated reduction. However, the use of toxic and explosive reagents, the generation of stoichiometric metal waste, poor selectivity and poor compatibility with low functional groups limit their practical application. The shortcomings of the above process can be effectively solved by transition metal-catalyzed dehalogenation and hydrogenation. In a large number of research reports, this process often requires the participation of precious metals (such as palladium, rhodium, ruthenium, platinum and nickel, etc.), which is costly. Summary of the invention

[0003] The object of the present invention is to provide a visible light-promoted method for the hydrodehalogenation of halogenated alkanes, which has simple operation, low cost and high safety.

[0004] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0005] The present invention provides a visible light-promoted method for the hydrodehalogenation of halogenated alkanes, comprising the following steps:

[0006] Halogenated alkane, titanium metal catalyst, organic amine compound, thiol compound and organic solvent are mixed, and a hydrogenation dehalogenation reaction is carried out under visible light irradiation in a protective atmosphere to obtain an alkane compound corresponding to the halogenated alkane.

[0007] Preferably, the halogenated alkane has a structure shown in Formula 1:

[0008]

[0009] In formula 1, R 1 includes aryl, substituted aryl, heteroaryl or hydrogen; R 2 includes alkyl, aryl or hydrogen; or R 1 and R 2 is independently cycloalkyl; X includes chlorine or bromine.

[0010] Preferably, the substituents in the substituted aryl include methyl, tert-butyl, phenyl, methylthio, methoxy, benzyloxy, dibenzylamino, chlorine, bromine, iodine, ester, cyano, hydroxymethyl or methyl acrylate substituents; the heteroaryl includes quinoline or indole.

[0011] Preferably, the titanium metal catalyst comprises bis(cyclopentadienyl)titanium dichloride or bis(pentamethylcyclopentadienyl)titanium dichloride.

[0012] Preferably, the organic amine compound includes N,N-diisopropylethylamine, triethylamine, N,N-dicyclohexylmethylamine, dibenzylamine, dicyclohexylamine or tribenzylamine.

[0013] Preferably, the thiol compound includes ethyl mercaptoacetate, benzyl mercaptan, tert-butyl mercaptan or ethyl mercaptan; and the organic solvent is tetrahydrofuran, dichloromethane, toluene, acetonitrile, methyl tert-butyl ether or n-hexane.

[0014] Preferably, the molar ratio of the halogenated alkane, the titanium metal catalyst, the organic amine compound and the thiol compound is 1:0.1:(1-3):2.

[0015] Preferably, the protective atmosphere is a nitrogen atmosphere or an argon atmosphere.

[0016] Preferably, the light source used for the visible light illumination condition is blue light, white light, yellow light, green light or purple light, and the power of the light source is 40W.

[0017] Preferably, the temperature of the hydrodehalogenation reaction is room temperature, and the time is 1 to 10 hours.

[0018] The present invention provides a visible light-promoted method for the hydrodehalogenation of halogenated alkanes, comprising the following steps: mixing halogenated alkanes, titanium metal catalysts, organic amine compounds, thiol compounds and organic solvents, and performing a hydrodehalogenation reaction under visible light illumination in a protective atmosphere to obtain an alkane compound corresponding to the halogenated alkanes. The present invention performs the hydrodehalogenation of halogenated alkanes under visible light illumination, and initiates free radicals under the promotion of visible light to achieve the cleavage of the carbon-halogen bond of the halogenated alkanes to generate alkyl free radicals, and at the same time, utilizes thiol to provide a hydrogen source to generate a reduction hydrogenation product, and the addition of organic amines is conducive to the capture of the halogen free radicals generated by the reaction, thereby increasing the reaction rate and achieving a high yield.

[0019] The present invention uses thiol as a hydrogen source and has good tolerance to reducible functional groups such as carbon-carbon double bonds, ester groups and cyano groups, and thus has good functional group tolerance and a wide substrate range.

[0020] The present invention uses a relatively cheap titanium metal catalyst (pre-transition metal) that is widely present in nature to achieve hydrogenation and dehalogenation of halogenated alkanes under the promotion of visible light, which can not only reduce the reaction cost, but also make the reaction process more gentle, avoid high temperature and high pressure, and increase the safety of operation. In addition, the chemical reaction promoted by visible light has mild reaction conditions, usually room temperature, and can achieve many reaction processes that are difficult to achieve with thermal reactions. Therefore, the method of the present invention is simple to operate and has mild reaction conditions (reaction can occur at room temperature).

[0021] The reaction product of the present invention has good selectivity and single product, which is conducive to separation and purification of the product. DETAILED DESCRIPTION

[0022] The present invention provides a visible light-promoted method for the hydrodehalogenation of halogenated alkanes, comprising the following steps:

[0023] Halogenated alkane, titanium metal catalyst, organic amine compound, thiol compound and organic solvent are mixed, and a hydrogenation dehalogenation reaction is carried out under visible light irradiation in a protective atmosphere to obtain an alkane compound corresponding to the halogenated alkane.

[0024] In the present invention, unless otherwise specified, the required raw materials or instruments are commercially available products well known to those skilled in the art.

[0025] In the present invention, the halogenated alkane preferably has a structure shown in Formula 1:

[0026]

[0027] In formula 1, R 1 includes aryl, substituted aryl, heteroaryl or hydrogen; R 2 includes alkyl, aryl or hydrogen; or R 1 and R 2 is independently cycloalkyl; X includes chlorine or bromine.

[0028] In the present invention, the substituents in the substituted aryl preferably include methyl, tert-butyl, phenyl, methylthio, methoxy, benzyloxy, dibenzylamino, chlorine, bromine, iodine, ester, cyano, hydroxymethyl or methyl acrylate substituents; in the present invention, the heteroaryl preferably includes quinoline or indole. The halogenated alkanes in the present invention are all commercially available products well known in the art.

[0029] In the present invention, the halogenated alkane is preferably p-methylbenzyl bromide, p-methylbenzyl chloride, benzyl bromide, benzyl chloride, 3-methylbenzyl bromide, p-tert-butylbenzyl bromide, p-tert-butylbenzyl chloride, p-phenylbenzyl bromide, 3-methoxybenzyl bromide, 3-methoxybenzyl chloride, 3-benzyloxybenzyl bromide, p-methylthiobenzyl bromide, 3-bromomethylbenzoic acid methyl ester, p-chloromethylbenzoic acid methyl ester, 3-cyanobenzyl bromide, 3-cyanobenzyl chloride, p-chlorobenzyl bromide, p-bromobenzyl bromide, p-bromobenzyl chloride, 3-bromobenzyl bromide, p-iodobenzyl bromide, 3-chlorobenzyl bromide, 3-chlorobenzyl chloride, 4- (Bromomethyl)-N,N-diphenylaniline, p-hydroxymethylbenzyl bromide, methyl p-methylcinnamate, methyl 4'-(bromomethyl)biphenyl-2-carboxylate, 4'-bromomethyl-2-biphenylnitrile, 2-bromomethylnaphthalene, 2-chloromethylnaphthalene, 1-bromo-2-bromomethylnaphthalene, 2-bromomethylquinoline, tert-butyl 3-bromomethyl-indole-1-carboxylate, dichlorobiphenylbenzyl, p-dibenzyl bromide, 1-bromoethylbenzene, 1-chloroethylbenzene, triphenylmethane, triphenylmethane chloride, bromocycloheptane or 2-bromooctane.

[0030] In the present invention, the titanium metal catalyst preferably includes bis(cyclopentadienyl)titanium dichloride or bis(pentamethylcyclopentadienyl)titanium dichloride.

[0031] In the present invention, the organic amine compound preferably includes N,N-diisopropylethylamine, triethylamine, N,N-dicyclohexylmethylamine, dibenzylamine, dicyclohexylamine or tribenzylamine. In the present invention, the organic amine compound is conducive to the capture of the halogen free radicals generated by the reaction, thereby increasing the reaction rate.

[0032] In the present invention, the thiol compound includes ethyl mercaptoacetate, benzyl mercaptan, tert-butyl mercaptan or ethyl mercaptan. The present invention utilizes the thiol compound as a hydrogen source.

[0033] In the present invention, the molar ratio of the halogenated alkane, the titanium metal catalyst, the organic amine compound and the thiol compound is preferably 1:0.1:(1-3):2, and more preferably 1:0.1:(2-3):2.

[0034] In the present invention, the organic solvent is preferably tetrahydrofuran, dichloromethane, toluene, acetonitrile, methyl tert-butyl ether or n-hexane; the volume ratio of the molar amount of the halogenated alkane to the organic solvent is preferably 0.2 mmol: (0.2-1) mL.

[0035] The present invention has no particular limitation on the mixing of the halogenated alkane, titanium metal catalyst, organic amine compound, thiol compound and organic solvent. The materials can be mixed uniformly according to a process well known in the art.

[0036] In the present invention, the protective atmosphere is preferably a nitrogen atmosphere or an argon atmosphere; the pressure of the protective atmosphere is preferably 1 atm.

[0037] In the present invention, the light source used for the visible light illumination condition is preferably blue light, white light, yellow light, green light or purple light, and the power of the light source is preferably 40w; the equipment used to provide the light source is preferably a commercially available photoreactor. In an embodiment of the present invention, it is specifically a 40w photoreactor produced by Geao Chemical, each reactor is composed of 8 5w lamp beads. The present invention utilizes a light source and a titanium metal catalyst to facilitate the generation of free radicals and realize a hydrodehalogenation reaction.

[0038] In the present invention, the temperature of the hydrodehalogenation reaction is preferably room temperature, and the time is preferably 1 to 10 hours, more preferably 2 to 4 hours; the hydrodehalogenation reaction is preferably carried out under stirring conditions. The present invention does not have any special restrictions on the stirring conditions, and the process familiar to those skilled in the art can be used.

[0039] In the present invention, the reaction formula of the hydrodehalogenation reaction is

[0040]

[0041] After the hydrodehalogenation reaction is completed, the present invention also preferably includes separating the obtained reaction product to obtain the alkane corresponding to the halogenated alkane. The present invention does not have any special limitation on the separation, and column chromatography and decompression spin drying well known to those skilled in the art can be used. In an embodiment of the present invention, the reaction product is specifically purified by silica gel column chromatography, and after elution with an eluent, the solvent is decompressed and spin dried; the eluent is petroleum ether or a petroleum ether-ethyl acetate mixed solvent; the volume ratio of petroleum ether to ethyl acetate in the petroleum ether-ethyl acetate mixed solvent is 10:1 or 20:1.

[0042] When the present invention does not carry out separation, it is preferred to obtain a reaction product system containing alkane compounds.

[0043] The technical solutions in the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] In the following examples, the light source used was a 40w photoreactor produced by Geao Chemical, each reactor consisting of 8 5w lamp beads;

[0045] In the embodiments of the present invention, in Examples 1 to 30, 32, 33, 35 to 46, 52, 53, 58 to 60, 63, and 64, no separation was performed, and a product system containing alkane compounds was directly obtained. Since the product had a low boiling point, the reaction system was analyzed by GC-MS to confirm the formation of the target product, and the yield of the alkane compounds in the product system was determined by gas phase detection (dodecane as an internal standard) or nuclear magnetic resonance analysis (benzyl benzoate as an internal standard).

[0046] Example 1

[0047] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.6mmol, 77.4mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added into a 10mL quartz reaction bottle and stirred for 10h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing the structural compound represented by formula 3a (p-xylene).

[0048] The yield was 96% as determined by GC-MS.

[0049] The chemical reaction formula of the above preparation process is:

[0050]

[0051] Example 2

[0052] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.6mmol, 77.4mg), ethyl thioglycolate (denoted as 2b, 0.4mmol, 42.4mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound (p-xylene) shown in formula 3a. The yield detected by GC-MS was 43%.

[0053] The chemical reaction formula of the above preparation process is:

[0054]

[0055] Example 3

[0056] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.6mmol, 77.4mg), benzyl mercaptan (denoted as 2c, 0.4mmol, 49.6mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound (p-xylene) shown in formula 3a. The yield detected by GC-MS was 88%.

[0057] The chemical reaction formula of the above preparation process is:

[0058]

[0059] Example 4

[0060] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.6mmol, 77.4mg), tert-butyl mercaptan (denoted as 2d, 0.4mmol, 36.0mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound shown in formula 3a (p-xylene). The yield detected by GC-MS was 80%.

[0061] The chemical reaction formula of the above preparation process is:

[0062]

[0063] Example 5

[0064] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), triethylamine (denoted as Et 3N, 0.6mmol, 60.6mg), ethanethiol (referred to as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (referred to as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (referred to as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing a structural compound (p-xylene) shown in formula 3a. The yield detected by GC-MS was 87%.

[0065] The chemical reaction formula of the above preparation process is:

[0066]

[0067] Example 6

[0068] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-dicyclohexylmethylamine (referred to as N,N-dicyclohexylmethylamine, 0.6mmol, 117.0mg), ethanethiol (referred to as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (referred to as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (referred to as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing a structural compound (p-xylene) shown in formula 3a. The yield detected by GC-MS was 89%.

[0069] The chemical reaction formula of the above preparation process is:

[0070]

[0071] Example 7

[0072] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), dibenzylamine (referred to as Dibenzylamine, 0.6mmol, 118.2mg), ethanethiol (referred to as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (referred to as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (referred to as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing a structural compound (p-xylene) shown in formula 3a. The yield detected by GC-MS was 83%.

[0073] The chemical reaction formula of the above preparation process is:

[0074]

[0075] Example 8

[0076] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), dicyclohexylamine (referred to as Dicyclohexylamine, 0.6mmol, 108.6mg), ethanethiol (referred to as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (referred to as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (referred to as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing a structural compound (p-xylene) shown in formula 3a. The yield detected by GC-MS was 81%.

[0077] The chemical reaction formula of the above preparation process is:

[0078]

[0079] Example 9

[0080] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), tribenzylamine (referred to as Tribenzylamine, 0.6mmol, 172.2mg), ethanethiol (referred to as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (referred to as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (referred to as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing a structural compound (p-xylene) shown in formula 3a. The yield detected by GC-MS was 79%.

[0081] The chemical reaction formula of the above preparation process is:

[0082]

[0083] Example 10

[0084] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2, 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.6mmol, 77.4mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and dichloromethane (denoted as DCM, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound shown in formula 3a (p-xylene). The yield detected by GC-MS was 73%.

[0085] The chemical reaction formula of the above preparation process is:

[0086]

[0087] Embodiment 11

[0088] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.6mmol, 77.4mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and toluene (denoted as Toluene, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound shown in formula 3a (p-xylene). The yield detected by GC-MS was 86%.

[0089] The chemical reaction formula of the above preparation process is:

[0090]

[0091] Example 12

[0092] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.6mmol, 77.4mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and acetonitrile (denoted as CH 3 CN, 1 mL) was added into a 10 mL quartz reaction bottle, and stirred for 10 h under argon (1 atm) atmosphere and 40 W blue light irradiation to obtain a product system containing a compound of formula 3a (p-xylene). The yield determined by GC-MS was 69%.

[0093] The chemical reaction formula of the above preparation process is:

[0094]

[0095] Example 13

[0096] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.6mmol, 77.4mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and methyl tert-butyl ether (denoted as MTBE, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound shown in formula 3a (p-xylene). The yield detected by GC-MS was 86%.

[0097] The chemical reaction formula of the above preparation process is:

[0098]

[0099] Embodiment 14

[0100] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.6mmol, 77.4mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and n-hexane (denoted as Hexane, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound shown in formula 3a (p-xylene). The yield detected by GC-MS was 84%.

[0101] The chemical reaction formula of the above preparation process is:

[0102]

[0103] Embodiment 15

[0104] Bis(pentamethylcyclopentadienyl)titanium dichloride (denoted as Cp* 2 TiCl 2, 0.02mmol, 7.8mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.6mmol, 77.4mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound (p-xylene) shown in formula 3a. The yield detected by GC-MS was 84%.

[0105] The chemical reaction formula of the above preparation process is:

[0106]

[0107] Example 16

[0108] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.2mmol, 25.8mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound (p-xylene) shown in formula 3a. The yield detected by GC-MS was 83%.

[0109] The chemical reaction formula of the above preparation process is:

[0110]

[0111] Embodiment 17

[0112] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound (p-xylene) shown in formula 3a. The yield detected by GC-MS was 94%.

[0113] The chemical reaction formula of the above preparation process is:

[0114]

[0115] Embodiment 18

[0116] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 1h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound shown in formula 3a (p-xylene). The yield detected by GC-MS was 83%.

[0117] The chemical reaction formula of the above preparation process is:

[0118]

[0119] Embodiment 19

[0120] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound shown in formula 3a (p-xylene). The yield detected by GC-MS was 96%.

[0121] The chemical reaction formula of the above preparation process is:

[0122]

[0123] Embodiment 20

[0124] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2, 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 4h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound shown in formula 3a (p-xylene). The yield detected by GC-MS was 98%.

[0125] The chemical reaction formula of the above preparation process is:

[0126]

[0127] Embodiment 21

[0128] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40w white light irradiation to obtain a product system containing the structural compound shown in formula 3a (p-xylene). The yield detected by GC-MS was 83%.

[0129] The chemical reaction formula of the above preparation process is:

[0130]

[0131] Embodiment 22

[0132] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40w yellow light irradiation to obtain a product system containing the structural compound (p-xylene) shown in formula 3a. The yield detected by GC-MS was 92%.

[0133] The chemical reaction formula of the above preparation process is:

[0134]

[0135] Embodiment 23

[0136] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40w green light irradiation to obtain a product system containing the structural compound shown in formula 3a (p-xylene). The yield detected by GC-MS was 85%.

[0137] The chemical reaction formula of the above preparation process is:

[0138]

[0139] Embodiment 24

[0140] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-methylbenzyl bromide (denoted as 1a, 0.2mmol, 37.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under 40w purple light irradiation under argon (1atm) atmosphere to obtain a product system containing the structural compound (p-xylene) shown in formula 3a. The yield detected by GC-MS was 97%.

[0141] The chemical reaction formula of the above preparation process is:

[0142]

[0143] Embodiment 25

[0144] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2, 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-methylbenzyl chloride (denoted as 1b, 0.2mmol, 28.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound (p-xylene) shown in formula 3a. The yield detected by GC-MS was 93%.

[0145] The chemical reaction formula of the above preparation process is:

[0146]

[0147] Embodiment 26

[0148] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), benzyl bromide (denoted as 1c, 0.2mmol, 34.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound (toluene) shown in formula 3c. The yield detected by GC-MS was 92%.

[0149] The chemical reaction formula of the above preparation process is:

[0150]

[0151] Embodiment 27

[0152] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), benzyl chloride (denoted as 1d, 0.2mmol, 25.2mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing the structural compound (toluene) shown in formula 3c. The yield detected by GC-MS was 85%.

[0153] The chemical reaction formula of the above preparation process is:

[0154]

[0155] Embodiment 28

[0156] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 3-methylbenzyl bromide (denoted as 1e, 0.2mmol, 37.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing a structural compound (meta-xylene) shown in formula 3e. The yield detected by GC-MS was 89%.

[0157] The chemical reaction formula of the above preparation process is:

[0158]

[0159] Embodiment 29

[0160] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-tert-butylbenzyl bromide (denoted as 1f, 0.2mmol, 45.2mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing the structural compound shown in formula 3f (p-tert-butyltoluene). The yield of NMR analysis was 80%.

[0161] The chemical reaction formula of the above preparation process is:

[0162]

[0163] Embodiment 30

[0164] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2, 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-tert-butylbenzyl chloride (denoted as 1g, 0.2mmol, 36.4mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing the structural compound shown in formula 3f (p-tert-butyltoluene). The yield of NMR analysis was 85%.

[0165] The chemical reaction formula of the above preparation process is:

[0166]

[0167] Embodiment 31

[0168] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-phenylbenzyl bromide (denoted as 1h, 0.2mmol, 49.2mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation, and then the reaction was purified by silica gel column chromatography, and after elution with petroleum ether as eluent, the solvent was decompressed and dried to obtain a compound having the structure shown in formula 3h (p-phenyltoluene). The isolation yield was 86%.

[0169] The chemical reaction formula of the above preparation process is:

[0170]

[0171] The characterization data are: 1 H NMR(400MHz,Chloroform-d)δ7.65(dd,J=8.3,1.3Hz,2H),7.56(d,J=8.1Hz,2H), 7.49(t,J=7.6Hz,2H),7.38(t,J=7.4Hz,1H),7.31(d,J=7.9Hz,2H),2.46(s,3H). 13 C NMR (101MHz, Chloroform-d) δ 141.3, 138.5, 137.1, 129.6, 128.8, 127.1, 127.1, 21.2.

[0172] Embodiment 32

[0173] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 3-methoxybenzyl bromide (denoted as 1i, 0.2mmol, 40.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound shown in formula 3i (3-methoxytoluene). The yield of nuclear magnetic analysis was 72%.

[0174] The chemical reaction formula of the above preparation process is:

[0175]

[0176] Embodiment 33

[0177] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 3-methoxybenzyl chloride (denoted as 1j, 0.2mmol, 31.2mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound shown in formula 3i (3-methoxytoluene). The yield of nuclear magnetic analysis was 98%.

[0178] The chemical reaction formula of the above preparation process is:

[0179]

[0180] Embodiment 34

[0181] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2, 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 3-benzyloxybenzyl bromide (denoted as 1k, 0.2mmol, 55.2mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation, and then the reaction product was purified by silica gel column chromatography, and after elution with petroleum ether as eluent, the solvent was decompressed and dried to obtain a compound having the structure shown in formula 3k (3-benzyloxytoluene). The isolation yield was 92%.

[0182] The chemical reaction formula of the above preparation process is:

[0183]

[0184] The characterization data are: 1 H NMR(400MHz,Chloroform-d)δ7.41(d,J=7.3Hz,2H),7.36(t,J=7.4Hz,2H),7.30(t ,J=7.1Hz,1H),7.15(t,J=7.9Hz,1H),6.87–6.70(m,3H),5.02(s,2H),2.31(s,3H). 13 C NMR (101MHz, Chloroform-d) δ159.0,139.6,137.3,129.3,128.7,128.0,127.6,121.9,115.8,111.8,69.9,21.6.

[0185] Embodiment 35

[0186] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-methylthiobenzyl bromide (denoted as 1l, 0.2mmol, 43.2mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing the structural compound shown in formula 3l (p-methylthiotoluene). The yield of nuclear magnetic analysis was 76%.

[0187] The chemical reaction formula of the above preparation process is:

[0188]

[0189] Embodiment 36

[0190] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), methyl 3-bromomethylbenzoate (denoted as 1m, 0.2mmol, 45.6mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound shown in formula 3m (methyl 3-methylbenzoate). The yield of nuclear magnetic analysis was 89%.

[0191] The chemical reaction formula of the above preparation process is:

[0192]

[0193] Embodiment 37

[0194] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), methyl p-chloromethylbenzoate (denoted as 1n, 0.2mmol, 36.8mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing the structural compound shown in formula 3n (methyl p-toluate). The yield of NMR analysis was 90%.

[0195] The chemical reaction formula of the above preparation process is:

[0196]

[0197] Embodiment 38

[0198] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2, 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 3-cyanobenzyl bromide (denoted as 1o, 0.2mmol, 39.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing the structural compound shown in formula 3o (3-cyanotoluene). The yield of NMR analysis was 68%.

[0199] The chemical reaction formula of the above preparation process is:

[0200]

[0201] Embodiment 39

[0202] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 3-cyanobenzyl chloride (denoted as 1p, 0.2mmol, 30.2mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing the structural compound shown in formula 3o (3-cyanotoluene). The yield of NMR analysis was 67%.

[0203] The chemical reaction formula of the above preparation process is:

[0204]

[0205] Embodiment 40

[0206] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-chlorobenzyl bromide (denoted as 1q, 0.2mmol, 40.8mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing the structural compound shown in formula 3q (p-chlorotoluene). The yield of NMR analysis was 74%.

[0207] The chemical reaction formula of the above preparation process is:

[0208]

[0209] Embodiment 41

[0210] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-bromobenzyl bromide (denoted as 1r, 0.2mmol, 49.6mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing the structural compound shown in formula 3r (p-chlorotoluene). The yield of NMR analysis was 88%.

[0211] The chemical reaction formula of the above preparation process is:

[0212]

[0213] Embodiment 42

[0214] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-bromobenzyl chloride (denoted as 1s, 0.2mmol, 40.8mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing the structural compound shown in formula 3r (p-bromotoluene). The yield of NMR analysis was 73%.

[0215] The chemical reaction formula of the above preparation process is:

[0216]

[0217] Embodiment 43

[0218] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2, 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 3-bromobenzyl bromide (denoted as 1t, 0.2mmol, 49.6mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing a structural compound shown in formula 3t (3-bromotoluene). The yield of NMR analysis was 85%.

[0219] The chemical reaction formula of the above preparation process is:

[0220]

[0221] Embodiment 44

[0222] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-iodobenzyl bromide (denoted as 1u, 0.2mmol, 59.2mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing a structural compound shown in formula 3u (p-iodotoluene). The yield of NMR analysis was 69%.

[0223] The chemical reaction formula of the above preparation process is:

[0224]

[0225] Embodiment 45

[0226] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 3-chlorobenzyl bromide (denoted as 1v, 0.2mmol, 40.8mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing the structural compound shown in formula 3v (3-chlorotoluene). The yield of nuclear magnetic analysis was 74%.

[0227] The chemical reaction formula of the above preparation process is:

[0228]

[0229] Embodiment 46

[0230] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 3-chlorobenzyl chloride (denoted as 1w, 0.2mmol, 30.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound shown in formula 3w (3-chlorotoluene). The yield of NMR analysis was 71%.

[0231] The chemical reaction formula of the above preparation process is:

[0232]

[0233] Embodiment 47

[0234] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 4-(bromomethyl)-N,N-diphenylaniline (denoted as 1x, 0.2mmol, 67.4mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation, and then the reaction product was purified by silica gel column chromatography, and after elution with petroleum ether as eluent, the solvent was decompressed and dried to obtain a compound having the structure shown in formula 3x (p-4-methyl-N,N-diphenylaniline). The isolation yield was 47%.

[0235] The chemical reaction formula of the above preparation process is:

[0236]

[0237] The characterization data are: 1 H NMR (400MHz, Chloroform-d) δ7.27–7.17(m,4H),7.06(td,J=5.3,2.5Hz,6H),7.03–6.92(m,4H),2.31(s,3H).13 C NMR (101MHz, Chloroform-d) δ 148.2, 145.4, 132.9, 130.1, 129.3, 125.1, 123.7, 122.4, 21.0.

[0238] Embodiment 48

[0239] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), p-hydroxymethylbenzyl bromide (denoted as 1y, 0.2mmol, 40.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation, and then the reaction was purified by silica gel column chromatography, and petroleum ether: ethyl acetate (V:V=10:1) was used as the eluent for elution, and the solvent was decompressed and dried to obtain a compound having the structure shown in formula 3y (p-methylbenzyl alcohol). The isolation yield was 88%.

[0240] The chemical reaction formula of the above preparation process is:

[0241]

[0242] The characterization data are: 1 H NMR (400MHz, Chloroform-d) δ7.24(d,J=7.9Hz,2H),7.16(d,J=7.9Hz,2H),4.61(s,2H),2.34(s,3H),1.90(s,1H). 13 C NMR (101MHz, Chloroform-d) δ 138.0, 137.5, 129.3, 127.2, 65.3, 21.3.

[0243] Embodiment 49

[0244] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2, 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), methyl p-methylcinnamate (denoted as 1z, 0.2mmol, 50.8mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation, and then the reaction was purified by silica gel column chromatography, and petroleum ether: ethyl acetate (V:V=20:1) was used as the eluent for elution, and the solvent was decompressed and dried to obtain a compound having the structure shown in formula 3z (methyl p-methylcinnamate). The isolation yield was 44%.

[0245] The chemical reaction formula of the above preparation process is:

[0246]

[0247] The characterization data are: 1 H NMR (400MHz, Chloroform-d) δ7.59(d,J=16.0Hz,1H),7.34(d,J=8.1Hz,2H),7.11(d,J=7.9Hz,2H),6.32(d,J=16.0Hz,1H),3.72(s,3H),2.29(s,3H). 13 CNMR(101MHz,Chloroform-d)δ167.8,145.0,140.9,131.8,129.7,128.2,116.8,51.8,21.6.

[0248] Embodiment 50

[0249] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 4'-(bromomethyl)biphenyl-2-carboxylic acid methyl ester (denoted as 1aa, 0.2mmol, 60.8mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation, and then the reaction was purified by silica gel column chromatography, and petroleum ether: ethyl acetate (V:V=20:1) was used as an eluent for elution, and the solvent was decompressed and dried to obtain a compound having the structure shown in formula 3aa (4'-(methyl)biphenyl-2-carboxylic acid methyl ester). The isolation yield was 87%.

[0250] The chemical reaction formula of the above preparation process is:

[0251]

[0252] The characterization data are: 1 H NMR (400MHz, Chloroform-d) δ7.70(d,J=7.5Hz,1H),7.40(t,J=7.5Hz,1H),7.27(t,J=7.4Hz,2H),7.11(s,4H),3.56(s,3H),2.29(s,3H). 13 C NMR (101MHz, Chloroform-d) δ169.3,142.5,138.4,137.0,131.3,130.9,130.8,129.8,128.9,128.3,127.0,52.0,21.3.

[0253] Embodiment 51

[0254] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 4'-bromomethyl-2-biphenylnitrile (denoted as 1ab, 0.2mmol, 54.2mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation, and then the reaction was purified by silica gel column chromatography, and after elution with petroleum ether: ethyl acetate (V:V=20:1) as an eluent, the solvent was decompressed and dried to obtain a compound having the structure shown in formula 3ab (4'-methyl-2-biphenylnitrile). The isolation yield was 83%.

[0255] The chemical reaction formula of the above preparation process is:

[0256]

[0257] The characterization data are: 1 H NMR(400MHz,Chloroform-d)δ7.69–7.62(m,1H),7.53(td,J=7.7,1.3Hz,1H),7.39(dd ,J=14.7,7.7Hz,3H),7.32(td,J=7.7,1.1Hz,1H),7.21(d,J=7.9Hz,2H),2.33(s,3H). 13C NMR (101MHz, Chloroform-d) δ145.6,138.9,135.4,133.8,132.9,130.1,129.5,128.7,127.4,119.0,111.3,21.3.

[0258] Embodiment 52

[0259] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 2-bromomethylnaphthalene (denoted as 1ac, 0.2mmol, 44.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing a structural compound (2-methylnaphthalene) shown in formula 3ac. The yield of NMR analysis was 70%.

[0260] The chemical reaction formula of the above preparation process is:

[0261]

[0262] Embodiment 53

[0263] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 2-chloromethylnaphthalene (denoted as 1ad, 0.2mmol, 35.2mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing the structural compound (2-methylnaphthalene) shown in formula 3ac. The yield of NMR analysis was 77%.

[0264] The chemical reaction formula of the above preparation process is:

[0265]

[0266] Embodiment 54

[0267] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2, 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 1-bromo-2-bromomethylnaphthalene (denoted as 1ae, 0.2mmol, 59.6mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation, and then the reaction product was purified by silica gel column chromatography, and after elution with petroleum ether as eluent, the solvent was decompressed and dried to obtain a compound having the structure shown in formula 3ae (1-bromo-2-methylnaphthalene). The isolation yield was 67%.

[0268] The chemical reaction formula of the above preparation process is:

[0269]

[0270] The characterization data are: 1 H NMR(400MHz,Chloroform-d)δ8.28(d,J=8.6Hz,1H),7.76(d,J=8.1Hz,1H),7.68(d,J=8.3 Hz,1H),7.54(t,J=8.0Hz,1H),7.44(t,J=7.4Hz,1H),7.32(d,J=8.3Hz,1H),2.61(s,3H). 13 C NMR (101MHz, Chloroform-d) δ136.1,133.1,132.6,128.8,128.1,127.4,127.4,127.0,125.8,124.2,24.3.

[0271] Embodiment 55

[0272] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 2-bromomethylquinoline (denoted as 1af, 0.2mmol, 44.2mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation, and then the reaction was purified by silica gel column chromatography, and petroleum ether: ethyl acetate (V:V=10:1) was used as the eluent for elution, and the solvent was decompressed and dried to obtain a compound (2-methylquinoline) having the structure shown in formula 3af. The isolation yield was 93%.

[0273] The chemical reaction formula of the above preparation process is:

[0274]

[0275] The characterization data are: 1 H NMR(400MHz,Chloroform-d)δ8.02(dd,J=8.4,1.9Hz,2H),7.75(d,J=8.1Hz,1H),7.67( ddd,J=8.5,6.9,1.5Hz,1H),7.46(t,J=7.5Hz,1H),7.26(d,J=8.5Hz,1H),2.74(s,3H). 13 C NMR (101MHz, Chloroform-d) δ159.1,147.9,136.2,129.5,128.7,127.6,126.6,125.7,122.1,25.4.

[0276] Embodiment 56

[0277] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 61.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), tert-butyl 3-bromomethyl-indole-1-carboxylate (denoted as 1ag, 0.2mmol, 37.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation, and then the reaction was purified by silica gel column chromatography, and after elution with petroleum ether as eluent, the solvent was decompressed and dried to obtain a compound having the structure shown in formula 3ag (tert-butyl 3-methyl-indole-1-carboxylate). The isolation yield was 54%.

[0278] The chemical reaction formula of the above preparation process is:

[0279]

[0280] The characterization data are: 1 H NMR (400MHz, Chloroform-d) δ8.04(d,J=6.7Hz,1H),7.41(d,J=7.6Hz,1H),7.32–7.20(m,2H),7.19–7.11(m,1H),2.19(d,J=1.3Hz,3H),1.58(s,9H). 13CNMR(101MHz,Chloroform-d)δ150.0,135.6,131.6,124.3,122.9,122.4,119.0,116.5,115.3,83.3,28.7,9.7.

[0281] Embodiment 57

[0282] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.8mmol, 49.6mg), dichlorobenzyl biphenyl (denoted as 1ah, 0.2mmol, 50.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, stirred for 2h under argon (1atm) atmosphere and 40W blue light irradiation, and then the reaction product was purified by silica gel column chromatography, and after elution with petroleum ether as eluent, the solvent was decompressed and dried to obtain a compound (4,4'-dimethylbiphenyl) having the structure shown in formula 3ah. The isolation yield was 71%.

[0283] The chemical reaction formula of the above preparation process is:

[0284]

[0285] The characterization data are: 1 H NMR (400MHz, Chloroform-d) δ7.47 (d, J = 8.0 Hz, 4H), 7.22 (d, J = 7.9 Hz, 4H), 2.37 (s, 6H). 13 C NMR (101MHz, Chloroform-d) δ 138.4, 136.8, 129.6, 126.9, 21.2.

[0286] Embodiment 58

[0287] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2, 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.8mmol, 49.6mg), p-dibenzyl bromide (denoted as 1ai, 0.2mmol, 52.4mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing the structural compound (p-xylene) shown in formula 3aa. The yield detected by GC-MS was 65%.

[0288] The chemical reaction formula of the above preparation process is:

[0289]

[0290] Embodiment 59

[0291] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 1-bromoethylbenzene (denoted as 1aj, 0.2mmol, 36.8mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing a structural compound (ethylbenzene) shown in formula 3aj. The yield detected by GC-MS was 54%.

[0292] The chemical reaction formula of the above preparation process is:

[0293]

[0294] Embodiment 60

[0295] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 1-chloroethylbenzene (denoted as 1ak, 0.2mmol, 28.0mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 2h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound (ethylbenzene) shown in formula 3aj. The yield detected by GC-MS was 61%.

[0296] The chemical reaction formula of the above preparation process is:

[0297]

[0298] Embodiment 61

[0299] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), triphenylmethanebromide (denoted as 1al, 0.2mmol, 64.4mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, stirred for 2h under argon (1atm) atmosphere and 40W blue light irradiation, and then the reaction was purified by silica gel column chromatography, and after elution with petroleum ether as eluent, the solvent was decompressed and dried to obtain a compound having the structure shown in formula 3al (triphenylmethane). The isolation yield was 35%.

[0300] The chemical reaction formula of the above preparation process is:

[0301]

[0302] The characterization data are: 1 H NMR (400MHz, Chloroform-d) δ7.27 (t, J = 7.4Hz, 6H), 7.20 (t, J = 7.3Hz, 3H), 7.11 (d, J = 7.3Hz, 6H), 5.55 (s, 1H). 13 C NMR (101MHz, Chloroform-d) δ 144.0, 129.6, 128.4, 126.4, 57.0.

[0303] Embodiment 62

[0304] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2, 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), triphenylmethane chloride (denoted as 1am, 0.2mmol, 55.6mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, stirred for 2h under argon (1atm) atmosphere and 40W blue light irradiation, and then the reaction product was purified by silica gel column chromatography, and after elution with petroleum ether as eluent, the solvent was decompressed and dried to obtain a compound (triphenylmethane) having the structure shown in formula 3a1. The isolation yield was 78%.

[0305] The chemical reaction formula of the above preparation process is:

[0306]

[0307] The characterization data are: 1 H NMR (400MHz, Chloroform-d) δ7.27 (t, J = 7.4Hz, 6H), 7.20 (t, J = 7.3Hz, 3H), 7.11 (d, J = 7.3Hz, 6H), 5.55 (s, 1H). 13 C NMR (101MHz, Chloroform-d) δ144.0, 129.6, 128.4, 126.4, 57.0.

[0308] Embodiment 63

[0309] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl 2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), bromocycloheptane (denoted as 1an, 0.2mmol, 35.2mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40W blue light irradiation to obtain a product system containing a structural compound (cycloheptane) shown in formula 3an. The yield detected by GC-MS was 93%.

[0310] The chemical reaction formula of the above preparation process is:

[0311]

[0312] Embodiment 64

[0313] Bis(cyclopentadienyl)titanium dichloride (denoted as Cp 2 TiCl2 , 0.02mmol, 5.0mg), N,N-diisopropylethylamine (denoted as DIPEA, 0.4mmol, 51.6mg), ethanethiol (denoted as 2a, 0.4mmol, 24.8mg), 2-bromooctane (denoted as 1ao, 0.2mmol, 38.4mg) and tetrahydrofuran (denoted as THF, 1mL) were added to a 10mL quartz reaction bottle, and stirred for 10h under argon (1atm) atmosphere and 40w blue light irradiation to obtain a product system containing the structural compound shown in formula 3ao (n-octane). The yield detected by GC-MS was 40%.

[0314] The chemical reaction formula of the above preparation process is:

[0315]

[0316] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A visible light-promoted method for the hydrodehalogenation of halogenated alkanes, The following steps are involved: Mixing a halogenated alkane, a titanium metal catalyst, an organic amine compound, a thiol compound and an organic solvent, and performing a hydrodehalogenation reaction under visible light irradiation in a protective atmosphere to obtain an alkane compound corresponding to the halogenated alkane; The halogenated alkane is p-methylbenzyl bromide, p-methylbenzyl chloride, benzyl bromide, benzyl chloride, 3-methylbenzyl bromide, p-tert-butylbenzyl bromide, p-tert-butylbenzyl chloride, p-phenylbenzyl bromide, 3-methoxybenzyl bromide, 3-methoxybenzyl chloride, 3-benzyloxybenzyl bromide, p-methylthiobenzyl bromide, 3-bromomethylbenzoic acid methyl ester, p-chloromethylbenzoic acid methyl ester, 3-cyanobenzyl bromide, 3-cyanobenzyl chloride, p-chlorobenzyl bromide, p-bromobenzyl bromide, p-bromobenzyl chloride, 3-bromobenzyl bromide, p-iodobenzyl bromide, 3-chlorobenzyl bromide, 3-chlorobenzyl chloride, 4-(bromomethyl) )-N,N-diphenylaniline, p-hydroxymethylbenzyl bromide, methyl p-methylcinnamate, methyl 4'-(bromomethyl)biphenyl-2-carboxylate, 4'-bromomethyl-2-biphenylnitrile, 2-bromomethylnaphthalene, 2-chloromethylnaphthalene, 1-bromo-2-bromomethylnaphthalene, 2-bromomethylquinoline, tert-butyl 3-bromomethyl-indole-1-carboxylate, dichlorobiphenyl, p-dibenzyl bromide, 1-bromoethylbenzene, 1-chloroethylbenzene, triphenylmethane, triphenylmethane chloride, cycloheptane bromide or 2-bromooctane; The titanium metal catalyst is bis(cyclopentadiene)titanium dichloride or bis(pentamethylcyclopentadiene)titanium dichloride; The organic amine compound is N,N-diisopropylethylamine, triethylamine, N,N-dicyclohexylmethylamine, dibenzylamine, dicyclohexylamine or tribenzylamine; The thiol compound is ethyl mercaptoacetate, benzyl mercaptan, tert-butyl mercaptan or ethyl mercaptan; The light source used for the visible light illumination condition is blue light, white light, yellow light, green light or purple light, and the power of the light source is 40w.

2. The method according to claim 1, It is characterized in that The organic solvent is tetrahydrofuran, dichloromethane, toluene, acetonitrile, methyl tert-butyl ether or n-hexane.

3. The method according to claim 1, It is characterized in that The molar ratio of the halogenated alkane, the titanium metal catalyst, the organic amine compound and the thiol compound is 1:0.1:(1-3):

2.

4. The method according to claim 1, It is characterized in that The protective atmosphere is a nitrogen atmosphere or an argon atmosphere.

5. The method according to claim 1, It is characterized in that The temperature of the hydrodehalogenation reaction is room temperature, and the time is 1 to 10 hours.

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