Abstract: Cyclization reactions of epichlorohydrin and epibromohydrin with free and masked dianions allow for a convenient synthesis of a variety of products, such as 2-(alkylidene)tetrahydrofurans, which can be further funcionalized by hydrogenation or ring transformation reactions, cyclopropanes, γ-butyrolactams, oxazines, oxazolo[3,4-b]pyridazin-7-ones or 2-(alkylidene)thiazolidines. In general, the reactions proceed with very good regioselectivity.

Review: Synlett 2023, 34, 1953-1960.

Period of investigation: 1999 - 2006

Keywords: dianions; 1,3-dicarbonyl compounds; cyclizations; silyl enol ethers