Regio- and Diastereoselective Synthesis of Functionalized Cyclopentenones by Domino Michael-Ester-Wittig Reactions of (3-Alkoxycarbonyl-2-oxopropylidene)triphenylphosphoranes with Maleic Diesters - Langer, Peter; Kracke, Bettina (Synlett, 2001)