Rearrangement of N-acyl-3, 4-dihydro-1H-2, 1-benzoxazines to 2-substituted-4H-3, 1-benzoxazines through a retro-Diels–Alder extrusion of formaldehyde
…, KM Jones, IR McNee, CA Rowbottom
文献索引：Glover, Stephen A.; Jones, Katherine M.; McNee, Ian R.; Rowbottom, Colleen A. Journal of the Chemical Society. Perkin Transactions 2, 1996 , vol. 7, p. 1367 - 1376
Acyl-3, 4-dihydro-1-2, 1-benzoxazines (3) undergo a thermal decomposition involving loss of formaldehyde in a retro-Diels–Alder reaction. The resultant-acylazaxylylenes (4) undergo a 6π electrocyclisation to give 2-substituted-4-3, 1-benzoxazines (5) rather than a 4π electrocyclisation to give the-acyl-1, 2-dihydrobe
