Dimethyl Sulfate → HCID 13772019, compound

Participants

Reaction Conditions

Reaction Steps

Dimethyl sulfate (1.442 g, 1.08 ml, 11.43 mM) was added to 3-benzyl-5,6-dimethoxyquinazolin-2,4(1H, 3H)-dione (1.20 g, 3.7 mM). The mixture was heated to 80° C. (oil bath temperature) and then heated at 80°-84° C. for five minutes with vigorous stirring. A white solid was present at all times. Aqueous KOH (~15 ml of a 5N aqueous solution) was added dropwise at 80°-90° C. until the pH of the reaction mixture became basic and stayed basic. Addition of the aqueous KOH took ~20 minutes. A white solid was present during the addition. The mixture was cooled in an ice-H2O bath and the white solid filtered, washed well with H2O (20 ml) and dried to give 1.00 g crude product. mp 149°-152° C. Recrystallization from isopropanol (50 ml) afforded the title compound as a white solid; 0.80 g (66.1%); mp 153°-155° C. CDCl3 (TMS) 7.10-7.80 (m, 6H, 7-H, 10-H, 11-H, 12-H, 13-H, 14-H), 6.82 (d, 1H, J8,7 =10 Hz, 8-H), 5.25 (s, 2H, 9-H), 3.95 (s, 3H, 5 or 6-OCH3), 3.88 (s, 3H, 5 or 6-OCH3), 3.53 (s, 3H, 1-CH3), M+ 326.

Provenance & Evidence