Nucleophilic (phenylsulfonyl)difluoromethylation of alkyl halides using PhSO2CF2SiMe3: preparation of gem-difluoroalkenes and trifluoromethyl compounds
摘要:
Nucleophilic (phenylsulfonyl)difluoromethylation of both alkyl iodides and bromides was successfully accomplished by using CsF/15-crown-5 as an initiating system in DME, and the amount of 15-crown-5 was found to be critical to the yield of the product. The prepared (phenylsulfonyl)difluoromethylated alkanes were converted into gem-difluoroalkenes by a base-mediated 1,2-elimination reaction, and the latter species could be further transformed into trifluoromethyl compounds in the presence of KF/18-crown-6 or TBAF. (C) 2010 Elsevier Ltd. All rights reserved.
Nucleophilic Difluoromethylation of Primary Alkyl Halides Using Difluoromethyl Phenyl Sulfone as a Difluoromethyl Anion Equivalent
作者:G. K. Surya Prakash、Jinbo Hu、Ying Wang、George A. Olah
DOI:10.1021/ol048166i
日期:2004.11.1
efficient nucleophilic difluoromethylation of primary alkyl halides has been disclosed through a novel nucleophilic substitution-reductive desulfonylation strategy, usingdifluoromethylphenylsulfone as a difluoromethyl anion ("CF(2)H(-)") equivalent.
Nucleophilic substitution reactions of difluorormethyl phenyl sulfone with alkyl halides leading to the facile synthesis of terminal 1,1-difluoro-1-alkenes and difluoromethylalkanes
申请人:Prakash Surya G. K.
公开号:US20060052643A1
公开(公告)日:2006-03-09
(Benzenesulfonyl)difluoromethyl anion, in situ generated from difluoromethyl phenyl sulfone and a base, was found to easily undergo nucleophilic substitution reactions (S
N
2) with primary alkyl halides, elemental halogens, and perfluoroalkyl halides with good selectivity. The formed (benzenesufonyl)difluoromethylalkanes are useful intermediates for the facile preparation of 1,1-difluoro-1-alkenes and difluorometbylalkanes. Thus, difluoromethyl phenyl sulfone acts as both “CF
2
═” and “CF
2
H
−
” synthons.
[EN] NUCLEOPHILIC SUBSTITUTION REACTIONS OF DIFLUOROMETHYL PHENYL SULFONE WITH ALKYL HALIDES LEADING TO THE FACILE SYNTHESIS OF TERMINAL 1,1-DIFLUORO-1-ALKENES AND DIFLUOROMETHYLALKANES<br/>[FR] REACTIONS DE SUBSTITUTION NUCLEOPHILIQUE DU DIFLUOROMETHYL- PHENYLSULFONE PAR DES HALOGENURES D'ALKYLE CONDUISANT A UNE SYNTHESE FACILE DE 1,1-DIFLUORO-1-ALCENES ET DE DIFLUOROMETHYLALCANES
申请人:UNIV SOUTHERN CALIFORNIA
公开号:WO2005097739A3
公开(公告)日:2006-05-18
Difluoromethyl Phenyl Sulfone, a Difluoromethylidene Equivalent: Use in the Synthesis of 1,1-Difluoro-1-alkenes
作者:G. K. Surya Prakash、Jinbo Hu、Ying Wang、George A. Olah