Thiazolylme-thylenetriphenylphosphorane and its benzo derivative: stable and practical Wittig reagents for the synthesis of vinylthiazoles and vinylbenzothiazoles. Two carbon homologation of aldehydes

The title thiazolyl phosphorane is a stable yet quite reactive Wittig-type reagent which upon reaction with various aldehydes affords vinylthiazoles, mainly or exclusively as E-isomers, in very good yields. Also the benzothiazolyl phosphorane derivative, unlike a literature report, prove to react with aldehydes. Vinylthiazoles subjected to formyl deblocking from thiazole nucleous afford two-carbon homologated satured aldehydes. As an example, one of these vinylthiazoles, viz. the β-phenyl derivative 8f, proves to add n-butyl lithium cuprate to give after the formyl deblocking 3-phenylheptanal. © 1988.