Cocatalysis by tetravalent tin compounds in phase-transfer catalyzed fluorination of alkyl halides and sulfonates
作者:Mieczysław Mąkosza、Robert Bujok
DOI:10.1016/s0040-4039(02)00376-3
日期:2002.4
Phase-transfer catalyzed fluorination of alkyl halides or sulfonates is co-catalyzed efficiently by triorganotin halides. The cocatalytic action is due to continuous formation of lipophilic hypervalent triorganodifluorostannate anions, which act as fluorinating agents in the organic phase.
Ni-catalyzed cross-electrophile coupling between vinyl/aryl and alkyl sulfonates: synthesis of cycloalkenes and modification of peptides
作者:Jicheng Duan、Yun-Fei Du、Xiaobo Pang、Xing-Zhong Shu
DOI:10.1039/c9sc03347e
日期:——
providing facile access to important building blocks. We also demonstrated the possibility to apply this method for late-stage modification of peptides. A broad range of functionalized alkyl groups could be selectively introduced into tyrosine in peptidesviaC–Cbondformation, which has been a challenge to the existing procedures.
Et3n.2Hf, a new convenient reagent for nucleophilic fluorine displacement reactions
作者:M.B. Giudicelli、D. Picq、B. Veyron
DOI:10.1016/s0040-4039(00)97108-9
日期:1990.1
Syntheses of fluoro compounds by nucleophilic substitution of bromides or methanesulfonates using Et3N.2HF as the reagent are reported. The formation of undesired elimination side products is limited. The synthesis of this new fluorinating reagent is also reported.
Tetrabutylammonium Butyldifluorodimethylsilicate and Difluorodimethylphenylsilicate, New Nucleophilic Fluorinating Reagents
作者:Jaroslav Kvíčala、Petr Mysík、Oldřich Paleta
DOI:10.1055/s-2001-12315
日期:——
Tetrabutylammonium butyldifluorodimethylsilicate (TAMBS, 1 a) and tetrabutylammonium difluorodimethylphenylsilicate (TAMPS, 1 b) were conveniently prepared from the corresponding substituted fluorodimethylsilanes and tetrabutylammonium fluoride. Both fluorosilicates 1 a, 1 b are powerful nucleophilic fluorinating reagents which transform primary or secondary halides, tosylates, or mesylates to the corresponding fluorides in moderate to good yields.
四丁基丁基二氟二甲基硅酸铵(TAMBS,1 a)和四丁基二氟二甲基苯基硅酸铵(TAMPS,1 b)由相应的取代氟二甲基硅烷和四丁基氟化铵方便地制备而成。氟硅酸盐 1 a 和 1 b 都是强力的亲核氟化试剂,可将伯或仲卤化物、甲苯磺酸盐或甲磺酸盐转化为相应的氟化物,收率适中甚至很高。
Cocatalysis in phase-transfer catalyzed fluorination of alkyl halides and sulfonates
作者:M. Mąkosza、R. Bujok
DOI:10.1016/j.jfluchem.2004.12.003
日期:2005.2
cocatalytic system was used to synthesis of 1,1-difluoroalkanes in two steps from aldehydes. A new kind of PTC was elaborated in which Ph3SnF acts as phase transfer catalyst via continuous formation of potassium salts of diflurotriphenylstannate anions soluble in dipolar aprotic solvents. A new, simple and general method of synthesis of tetraalkylammonium and potassium salts of difluorotriorgano-tin, silicon