Hirohiko Sugimoto

Synthetic Application of 1,3-Dithiolium and 1,3-Oxathiolium Cations

Abstract 1,3-Dithiolium and 1,3-oxathiolium salts are positively charged 6φ electronically conjugated cations containing two hetero atoms in a five-membered ring. They exhibit a high reactivity toward nucleophiles. This study has shown that 1,3-dithiolium cations form an interesting class of compounds because of their non-benzenoid aromaticity and that 1,3-oxathiolium cations are highly versatile synthetic intermediates which can provide a number of novel heterocyclic compounds and their precursors depending on the nature of the nucleophiles and the reaction conditions.

Thiamin ylide: isolation and identification

The action of two equivalents of NaOEt on thiamin hydrochloride in EtOH gives a neutral compound. Spectroscopic data and its chemical behavior indicated that the compound is thiamin ylide 1. The chemical behaviors of 1 are entirely consistent with those of in situ generated thiamin ylide.