Intramolecular Tandem Seleno-Michael/Aldol Reaction: A Simple Route to Hydroxy Cyclo-1-ene-1-carboxylate Esters.

Intramolecular tandem seleno-Michael/aldol reaction followed by an oxidation-elimination process can be an efficient tool for the construction of hydroxy cyclo-1-ene-1-carboxylate esters from oxo-α,β-unsaturated esters. Generation of lithium selenolate from elemental selenium and n-BuLi provides a simple and efficient one-pot access to cyclic endo-Morita-Baylis-Hillman adducts.