Pd-Catalyzed Decarboxylative Cycloaddition of Vinylethylene Carbonates with Isothiocyanates.

An efficient route for formal [3 + 2] cycloaddition of vinylethylene carbonates with isothiocyanates was developed for the synthesis of 1,3-oxazolidine-2-thione derivatives. The zwitterionic π-allyl palladium intermediates formed in situ by decarboxylation of VECs acted as the three-membered synthons. In this transformation, the C-N bond formation was selectively realized over the C-S bond formation.