Abstract
Several procedures have been developed for the synthesis of α, β-unsaturated ketones via β-elimination of suitable derivatives (X=sulfoxy1-, selenoxy2,3-, bromo4-). In general, this approach requires position specific enolate formation, and as a result, is intrinsically inapplicable to unsymmetric acyclic substrates, owing to little position selectivity if both αand α′-positions are available for deprotonation.