Synthesis and reactivity studies of α,α-difluoromethylphosphinates
摘要:
The preparation and reactivity of some a,alpha-difluorophosphinates are investigated. Alkylation of H-phosphinates with LiHMDS and ClCF2H gives the corresponding alpha,alpha-difluorophosphinates in good yield. Deprotonation of these reagents with alkyllithium or LDA is then studied. Subtle electronic effects translate into significant differences in the deprotonation/alkylation of the two 'Ciba-Geigy reagents' (EtO)(2)CRP(O)(OEt)H (R=H, Me). On the other hand, attempted methylation of difluoromethyl-octyl-phosphinic acid butyl ester resulted in the exclusive alkylation of the octyl chain. Finally, reaction with carbonyl compounds results in the formation of 1,1 -difluoro-2-phosphinoyl compounds. (C) 2010 Elsevier Ltd. All rights reserved.