N-Alkylation
of 2-azidobenzenesulfonamide with 5-bromopent-1-ene
gave an
N
-pentenyl sulfonamide, which underwent intramolecular
aminohydroxylation to give an
N
-(2-azidoaryl)sulfonyl
prolinol, a precursor for the synthesis of a pyrrolobenzothiadiazepine.
The attempted N-alkylation of 2-azidobenzamide gave a separable mixture
(∼1:1) of a benzotriazinone and a quinazolinone in a 72% combined
yield. Other primary alkyl halides (3 examples) gave similar mixtures
of benzotriazinones and quinazolinones. Benzylic, allylic, and secondary
and tertiary alkyl halides (5 examples) gave only benzotriazinones
in moderate yields. The results of mechanistic studies show the likely
involvement of nitrene intermediates in the quinazolinone pathway
and a second pathway involving a dimethylsulfoxide or dimethylsulfide-mediated
conversion of 2-azidobenzamide into benzotriazinones.