Abstract
Methyl 3-hydroxy-2-methyl-1,1,4-trioxo-1,2,3,4-tetrahydro-1 lambda(6)-benzo[e][1,2]thiazine-3-carboxylate was synthesized in single step through in situ bromination of methyl 2-methyl-1,1,4-trioxo-1,2,3,4-tetrahydro-1 lambda(6)-benzo[e][1,2]thiazine-3-carboxylate using dibenzoyl peroxide & N-bromosuccinamide and was crystallized in acetone-ethyl acetate mixture (1:1). However, crystallization in methanol converted the title compound to methyl 3-methoxy-2-methyl-1,1,4-trioxo-1,2,3,4-tetrahydro-1 lambda(6)-benzo[e][1,2]thiazine-3-carboxylate, an unsymmetrical ether. The titled compound C11H11NO6S (3) crystallized in nonoclinic space group P2(1)/c whereas, the compound C12H13NO6S (4) crystallized in triclinic space group P-1. X-ray studies shows that the molecules of 1 are linked into a one-dimensional framework structure by C-H center dot center dot center dot O and O-H center dot center dot center dot O hydrogen bonds, while in 4, intermolecular C-H center dot center dot center dot O and C-H center dot center dot center dot pi hydrogen bonds and a pi center dot center dot center dot pi interaction result in the formation of infinite chains running along the [010] and [001] directions.