Epoxides are useful intermediates in organic synthesis because of their easy accessibility and high reactivity. A number of syntheses of fiveYmembered heterocycles from epoxides have been reported in the literature.1-4 Baba et al.4 have reported the cycloaddition of epoxides with heterocumulenes promoted by high-coordinated trialkyltin complexes, whilst Shibata et al.3 have reported the same reactions using organotin iodine-Lewis base complexes as catalysts. We have reported ...
