Unusual, strained heterocycles: 3-alkylidene-2-methyleneoxetanes from Morita-Baylis-Hillman-type adducts.

[reaction: see text] 3-Alkylidene-2-methyleneoxetanes have been prepared by treating alpha-alkylidene-beta-lactones, derived from Morita-Baylis-Hillman-type adducts, with dimethyltitanocene. Preliminary studies of the reactivity of these little known, strained heterocycles are also described.