Abstract

Stirred 10.25 g ClO3F in 300 ml MePh at -70 Deg, under N, was treated with 160 ml 0.41M triphenylphosphonium methylide to give 98% [Ph3P+CH2F]ClO3- (I), m. 131-4 Deg (CH2Cl2-AcOH-EtOAc). Satd. 1 equiv. I in Me2CO treated with 1.25 equivs. NaI in Me2CO gave 90% [Ph3P+CH2F]I- (II), m. 169-71 Deg. Stirred 29.5 g II in 450 ml tetrahydrofuran at -78 Deg was treated dropwise with LiBr-contg. LiPh in Et2O to give Ph3P+C-HF which reacted with BzH to give 65% PhCH:CHF (50:50 cis-trans ratio), b65 71-4 Deg. Similarly was prepd. C5H11CH:CHF 45:55 cis-trans ratio b. 100-4 Deg, as well as the following compds. in 50:50 cis-trans ratio: 3-F3CC6H4CH:CHF, 3-ClC6H4CH:CHF, b15 84-7 Deg, and III, m. 138-41 Deg, in 55, 25, 65 and 16% yields, resp. [on SciFinder (R)]

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