Stereoselective Cycloaddition of Nitrile Oxides to 4-Vinyl-Oxazolines and -Oxazolidines

Article abstract of DOI:10.1016/S0040-4039(00)93409-9

Cycloaddition of nitrile oxides to 4-vinyl-2-oxazoline 1 and to 4-vinyloxazolidine 2 afford diastereomeric mixtures of 2-isoxazolines in which the erythro product predominates (32-64percent d.e.).In contrast, the corresponding reactions with acyclic analogue 3 favoured the threo-adducts and were less selective (8-20percent d.e.).Key Words: 1,3-dipolar cycloaddition; nitrile oxides; isoxazolines