Norbornane and norbornene‐condensed dihydro‐1,3‐oxazines 1–6 were converted with salicyl chloride to 5,8‐methanobenzoxazino[2,1–6]‐ and ‐[2,3‐b]‐1,3‐benzoxazin‐4‐ones 7–12. The addition takes place to the C N bond: after acylation, the intermediate is stabilized through cyclization to the aryl‐substituted carbon by hydrogen chloride elimination. Diastereomers containing the oxazine rings in isomeric positions could be isolated in two cases. This is the first example of the isolation of diastereomers in such a salicyl chloride reaction. In contrast with earlier findings with reactions of related systems, no addition to the C C bond could be observed. The steric structures of the compounds were elucidated by ir, 1H‐ and 13C‐nmr spectroscopy.
ASJC Scopus subject areas
- Organic Chemistry