2453-46-5Relevant articles and documents
Highly selective halogenation of unactivated C(sp3)-H with NaX under co-catalysis of visible light and Ag@AgX
Liu, Shouxin,Zhang, Qi,Tian, Xia,Fan, Shiming,Huang, Jing,Whiting, Andrew
, p. 4729 - 4737 (2018/10/23)
The direct selective halogenation of unactivated C(sp3)-H bonds into C-halogen bonds was achieved using a nano Ag/AgCl catalyst at RT under visible light or LED irradiation in the presence of an aqueous solution of NaX/HX as a halide source, in air. The halogenation of hydrocarbons provided mono-halide substituted products with 95% selectivity and yields higher than 90%, with the chlorination of toluene being 81%, far higher than the 40% conversion using dichlorine. Mechanistic studies demonstrated that the reaction is a free radical process using blue light (450-500 nm), with visible light being the most effective light source. Irradiation is proposed to cause AgCl bonding electrons to become excited and electron transfer from chloride ions induces chlorine radical formation which drives the substitution reaction. The reaction provides a potentially valuable method for the direct chlorination of saturated hydrocarbons.
A alkane halogenation method (by machine translation)
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Paragraph 0044; 0045, (2017/07/21)
The invention relates to a cycloalkane of halogenation method, comprises the following steps: S1: taking inorganic hydrohalide salt M+ X- And the inorganic acid or organic acid, stirring to dissolve in water, containing the halide X- Aqueous solution; S2: light in the reactor will be put aqueous solution, add nanometer metal/semiconductor composite material photocatalyst, phase transfer catalyst and reaction substrate cycloalkane; S3: under the stirring condition, in the sunlight or 300W xenon lamp or LED light shifted to catalytic reaction; S4: reaction after the fluid is static set, filtering and recycling photocatalyst, separating and recovering the aqueous phase and then, drying the organic phase, and the dried organic phase rectification separation purification, to obtain the corresponding organic halogenated product. The present invention provides a method halide of the cycloalkanes, low cost, the apparatus is simple and easy to operate, high selectivity, easy separation, can be large-scale production, is a novel, environmental protection, high selectivity, low energy consumption of the new organic halide, viable green channels, with potential industrial application value. (by machine translation)
Photoinduced, Copper-Catalyzed Carbon-Carbon Bond Formation with Alkyl Electrophiles: Cyanation of Unactivated Secondary Alkyl Chlorides at Room Temperature
Ratani, Tanvi S.,Bachman, Shoshana,Fu, Gregory C.,Peters, Jonas C.
supporting information, p. 13902 - 13907 (2016/01/15)
We have recently reported that, in the presence of light and a copper catalyst, nitrogen nucleophiles such as carbazoles and primary amides undergo C-N coupling with alkyl halides under mild conditions. In the present study, we establish that photoinduced, copper-catalyzed alkylation can also be applied to C-C bond formation, specifically, that the cyanation of unactivated secondary alkyl chlorides can be achieved at room temperature to afford nitriles, an important class of target molecules. Thus, in the presence of an inexpensive copper catalyst (CuI; no ligand coadditive) and a readily available light source (UVC compact fluorescent light bulb), a wide array of alkyl halides undergo cyanation in good yield. Our initial mechanistic studies are consistent with the hypothesis that an excited state of [Cu(CN)2]- may play a role, via single electron transfer, in this process. This investigation provides a rare example of a transition metal-catalyzed cyanation of an alkyl halide, as well as the first illustrations of photoinduced, copper-catalyzed alkylation with either a carbon nucleophile or a secondary alkyl chloride.
A facile and green protocol for nucleophilic substitution reactions of sulfonate esters by recyclable ionic liquids [bmim][X]
Liu, Yajun,Xu, Yongnan,Jung, Sun Ho,Chae, Junghyun
, p. 2692 - 2698,7 (2012/12/12)
Ionic liquids [bmim][X] (X = Cl, Br, I, OAc, SCN) are highly efficient reagents for nucleophilic substitution reactions of sulfonate esters derived from primary and secondary alcohols. The counter anions (X-) of the ionic liquids, [bmim][X], effectively replace the sufonates affording the corresponding substitution products such as alkyl halides, acetates, and thiocyanides in excellent yields. The newly developed protocol is very environmentally attractive because the reactions use stoichiometric amounts of ionic liquids as sole reagents in most cases and do not require additional solvents, any other activating reagents, non-conventional equipment, or special precautions. Moreover, these ionic liquids can be readily recycled without loss of reactivity, making the whole process greener.
A facile and green protocol for nucleophilic substitution reactions of sulfonate esters by recyclable ionic liquids [bmim][X]
Liu, Yajun,Xu, Yongnan,Jung, Sun Ho,Chae, Junghyun
, p. 2692 - 2698 (2013/01/15)
Ionic liquids [bmim][X] (X = Cl, Br, I, OAc, SCN) are highly efficient reagents for nucleophilic substitution reactions of sulfonate esters derived from primary and secondary alcohols. The counter anions (X-) of the ionic liquids, [bmim][X], effectively replace the sufonates affording the corresponding substitution products such as alkyl halides, acetates, and thiocyanides in excellent yields. The newly developed protocol is very environmentally attractive because the reactions use stoichiometric amounts of ionic liquids as sole reagents in most cases and do not require additional solvents, any other activating reagents, non-conventional equipment, or special precautions. Moreover, these ionic liquids can be readily recycled without loss of reactivity, making the whole process greener. Georg Thieme Verlag KG Stuttgart · New York.
Conversion of alcohols into alkyl chlorides using trichloroisocyanuric acid with triphenylphosphine
Hiegel, Gene A.,Rubino, Mark
, p. 2691 - 2694 (2007/10/03)
Trichloroisocyanuric acid with triphenylphosphine in anhydrous acetonitrile will convert alcohols into alkyl halides.
Surface-mediated reactions. 3. Hydrohalogenation of alkenes
Kropp, Paul J.,Daus, Kimberlee A.,Tubergen, Mark W.,Kepler, Keith D.,Wilson, Vincent P.,Craig, Stephen L.,Baillargeon, Michelle M.,Breton, Gary W.
, p. 3071 - 3079 (2007/10/02)
Appropriately prepared silica gel and alumina have been found to mediate the addition of HCl, HBr, and HI to alkenes. The technique has been rendered even more convenient by the use of various organic and inorganic halides that undergo hydrolysis in the presence of silica gel or alumina to generate hydrogen halides in situ. Under these conditions alkenes such as cycloheptene (1), 1-octene (7), and 3,3-dimethyl-1-butene (15), which react with HCl only very slowly in solution, underwent rapid addition. 1-Octene (7) underwent ionic addition of HBr without competing radical addition. 1,2-Dimethylcyclohexane (24) afforded the syn addition product 25c, which underwent equilibration with the thermodynamically more stable isomer 25t. A mechanism for surface-mediated addition/elimination is proposed involving a stepwise transfer of H+ and X- from or to the surface in syn fashion, as shown in Scheme II.
Mechanism of Palladium(II)-Copper(II)-Mediated Demercuration of Cycloalkyl and Cycloalkylmethyl Systems
Wells, Adam P.,Kitching, William
, p. 2517 - 2519 (2007/10/02)
The palladium(II)-copper(II)-mediated demercuration of cycloalkyl- and cycloalkylmethylmercuric chlorides exhibit mechanistic changes as a function of ring size, with elimination-readdition of being important in cyclohexyl systems but direct carbocation formation dominating in cyclooctyl cases.
