Pyridine → HCID 20208336, compound

Participants

Reaction Steps

To a solution of 200 mg 2-methylamino-5-methyl-4H-3,1-benzoxazin-4-one, prepared as described in Example I, above, in 20 ml of dry tetrahydrofuran, was added 3 ml of acetic anhydride, 3 ml of pyridine and 25 mg of dimethylaminopyridine. The solution was stirred at room temperature for 3 days. The solvent was removed under reduced pressure, and remaining trace amounts of acetic anhydride and pyridine were removed by azeotroping with toluene. The residue was purified by column chromatography over silica gel (10% ethyl acetate:petroleum ether, 30°-60° C.) to yield 210 mg of 2-(N-methylacetylamino)-5-methyl-4H-3,1-benzoxazin-4-one, m.p. 108°-109° C., 'H NMR: (delta CDCl3); 2.6 (s, 3H, CH3 -Ar), 2.8 (s, 3H, CH3), 3.4 (s, 3H, NMe), 7.1-7.8 (m, 3H, Ar-H); IR: 1765, 1690, 1640, 1620, 1600 cm-1.

Provenance & Evidence