A New Reaction System for Horner-Wadsworth-Emmons Olefination of Optically Active 4-Hydroxy-2-oxo-alkylphosphonates and 4-Hydroxy-1-chloro-2-oxo-alkylphosphonates with Aliphatic Aldehydes - Xu, Chengfu; Yuan, Chengye (Synthesis, 2004)