摘要：

A new and general synthesis of ketene S,S-thioacetals (1) and ketene O.S-thioacetals (6) which involves the Horner-Wittig reaction of carbonyl compounds with the metallated S,S- and O,S-thioacetals of formyl-phosphonates (4 and 5) is described. The Horner-Wittig reaction of 4 with aromatic aldehydes can be carried out under two-phase conditions. The generation of the carbanions from 4 and 5 as well as the course of their reaction with carbonyl compounds were studied by the low temperature 31P NMR spectroscopy. It was found that S,S-thioacetals of formylphospbonates (4) are very easily metallated in contrast to O,S-thioacetals of formyl-phosphonates (5) which form the lithium derivatives only on treatment with t-butyllitnium. No evidence was obtained from 31P NMR spectra supporting the formation of the lithium derivatives of 0,0-acetals of formyl-phosphonates (12).

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