A theoretical model for the facial selectivity of N-dienyl oxazolidin-2-(thi)one and thiazolidin-2-thione 2a-c is presented. Our analysis provides a clear understanding of factors controlling stereoselectivity in reaction of these dienes, and allows predictions of high diastereoselectivity in the case of oxazolidin-2-thionyl diene (2b). The application of this diene to the synthesis of beta- and gamma-aminophosphonic derivatives is then investigated. Under classical conditions or under microwave activation, the D-A reaction of diene 2b leads to aminophosphonic chirons with high regio- and stereoselectivities. (C) 2009 Elsevier Ltd. All rights reserved.