The reaction of trialkylstannylmethyllithium with α,β-epoxy ketones. A preparative method of β, γ-unsaturated ketones by homologation of α, gb-unsaturated ketones
α, β-epoxy ketones 2, upon treatment with two equivalents of trialkylstannylmethyllithium 1, afforded cyclopropanols 3 as a single product in acyclic system, and a mixture of cyclopropanols 3 and methylene 1,2-diols 4 in cyclic system. Under acidic conditions, the cyclopropanols gave β, γ-unsaturated ketones 5 in good yields.