Solvent and substituent effects on rearrangement of 4-(4-X-phenyl)-2,7-dioxa-3-azabicyclo[3,3,0]oct-3-enes

Abstract

Preparation of the title compounds V is described. They give, on irradiation, the 2,3-dihydro--6H~1,3-oxazine derivatives VI as the main products besides the tetrahydrofuro[3,4-d]oxazoline derivatives VII. The VI to VII product ratio depends on the substituent bound to the aromatic residue. Polar solvents favour formation of the VI derivatives in the order CI > H > CH 3 .