On the coupling reaction of lithium azaenolates of chiral oxazolines with carbonyl compounds

Optically pure chloromethyloxazolines have been prepared, lithiated and the n reacted with benzophenone to famish stereoselectively oxazolinyl oxiranes and formyl oxiranes. The stereoselection observed has been related to the geometry of the intermediate lithium azaenolates. Calculations have been ca rried out in order to evaluate the relative stability of the E and Z forms of the lithium azaenolates. The reaction of a lithium azaenolate with other ketones leading to oxazolinyl epoxides is also reported. (C) 2001 Elsevier Science Ltd. All rights reserved.