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A novel and efficient synthesis of alkyl thiocyanates from alkyl halides in water using phase transfer catalysts

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Chinese Chemical Letters 2011年第6期22卷 659-662页

作者： Maryam Gorjizadeh Soheil Sayyahi Department of Chemistry Islamic Azad University

1,4-Bis（triphenylphosphonium）-2-butene dichloride（BTPBDC） and 1,4-bis（triphenyl phosphonium）-2-butene dithiocyanate （BTPBDT） were prepared and used as phase-transfer *** halides were converted efficiently to the corresponding alkyl thiocyanates under mild reaction conditions in *** evidence for the formation of isothiocyanates as by-product of the reaction was observed.

关键词： alkyl thiocyanate alkyl halide 1 4-Bis(triphenylphosphonium)-2-butene dichloride 1 4-Bis(triphenyl-phosphonium)-2-butene dithiocyanate Phase transfer catalyst

Immobilization of HX:[Hmim]X as Halogenating Agent, Recyclable Catalyst and Medium for Conversion of Alcohols to alkyl halides

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Chinese Journal of Chemistry 2004年第7期22卷 619-621页

作者：吴海虹孙靖杨帆汤杰何鸣元 Department of Chemistry East China Normal University Shanghai 200062 China

HX is immobilized by reaction of halogen acid with methylimidazole, and the formed ionic liquid [Hmim]X was used as halogenating agent, catalyst as well as medium for conversion of alcohols to alkyl halides. Excellent yields were obtained. The halides produced could be easily separated from the reaction mixture via simple decantation, and the ionic liquid [Hmim]X could be regenerated conveniently by adding equivalent of halogen acids followed by removal of water.

关键词： halogenation ionic liquid alcohol alkyl halide

Elimination of HBr from CH_3Br by Cu^+ and Au^+:A DFT study

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Chinese Chemical Letters 2008年第7期19卷 881-884页

作者： Tao Hong Li Chuan Ming Wang Xiang Yi Liu Xiao Guang Xie Faculty of Chemistry Southwest Forestry University Kunming 650224 China Department of Biology Honghe University Menzi 661100 China Department of Chemistry Yunnan University Kunming 650091 China

The elimination of HBr from CH3Br by ground state of Cu＋ and Au＋ has been investigated by using DFT methods. A mechanism of one-step HBr elimination leading to CuCH2＋ was identified. For the formation of AuCH2＋, besides the one-step mechanism, another two-step HBr elimination pathway through a C-Br bond insertion intermediate was also found, and this pathway is energetically more favorable than the one-step mechanism. The calculated reaction energy barriers show that the formation of AuCH2＋ is energetically much more favorable than the formation of CuCH2＋. The experimental observations are well explained.

关键词： Copper and gold alkyl halide HBr elimination

A facile and convenient method for synthesis of alkyl thiocyanates under homogeneous phase transfer catalyst conditions

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Chinese Chemical Letters 2008年第11期19卷 1301-1304页

作者： Ali Reza Kiasat Rashid Badri Soheil Sayyahi Chemistry Department College of ScienceShahid Chamran UniversityAhvaz 61357-4-3169Iran

A simple and environmentally friendly method is described for the efficient conversion of alkyl halide to alkyl thiocyanate using tetrabutylammonium bromide （TBAB） as a phase transfer catalyst. The reactions occur in water and furnish the corresponding alkyl thiocyanate in high yields. No evidence for the formation of isothiocyanates as by-product of the reaction was observed and the products were obtained in pure form without further purification.

关键词： alkyl thiocyanate alkyl halide Tetrabutylammonium bromide Phase transfer catalyst Synthesis of alkyl thiocyanates