Investigation of 4H-3,1-benzoxazines

The alkylation and acylation of 2,4-disubstituted 1,2-dihydro-4H-3,1-benzoxazines were used to obtain N-methyl and N-acetyl derivatives of these compounds for the first time.1H NMR was used to reveal several conformational features of these compounds relative to their donor—acceptor properties at positions 2, 3, and 4 of the heterocycle.