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Synthesis and Reactivity Studies of ?,?-Difluoromethylphosphinates.

ABSTRACT: The preparation and reactivity of some ?,?-difluorophosphinates is investigated. Alkylation of H-phosphinates with LiHMDS and ClCF(2)H gives the corresponding ?,?-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.

SUBMITTER: Abrunhosa-Thomas I

PROVIDER: S-EPMC2921993 | biostudies-literature | 2010 Jun

REPOSITORIES: biostudies-literature

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Synthesis and Reactivity Studies of α,α-Difluoromethylphosphinates.

Abrunhosa-Thomas Isabelle I Coudray Laëtitia L Montchamp Jean-Luc JL

Tetrahedron 20100601 26

The preparation and reactivity of some α,α-difluorophosphinates is investigated. Alkylation of H-phosphinates with LiHMDS and ClCF(2)H gives the corresponding α,α-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-octy ...[more]

PMID: 20725593

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