Additions to cyclic nitrones: synthesis of a pyrrolo[1,2-b]-1,2-benzisoxazole

Abstract

5,5-Dimethyl-1-pyrroline 1-oxide has been condensed with a number of polarisable olefinic systems forming the expected pyrroloisoxazoles. Two isomeric products are possible depending on the polarisation of the nitrone; using nuclear magnetic resonance we were able to identify the isomers in a number of cases. With 2-cyclohexenone the cyclic nitrone formed a pyrrolo[1,2,-b]-1,2-benzisoxazol-9-one.