Water → 4,6-Dimethoxyisatoic anhydride

Participants

Reaction Steps

To a cooled (0° C.) brown solution of 4,6-dimethoxy anthranilic acid (76.0 g, 0.385 mol), [Newman, H.; Angier, R. B. J. Org. Chem., 1969, 34(11), 3484] in THF (1.3 L) was added triphosgene (40.0 g, 0.135 mol) in portions over a 20 min period. After 30 min, the reaction was warmed to room temperature and stirred for an additional 1.5 h. The reaction mixture was poured into cold (0° C.) water (4 L). Additional water (2 L) was added to facilitate the stirring of the thick solid formed. After stirring for 30 min, the reaction mixture was filtered to give a beige solid. The solid was washed with water, air-dried, and then dried under high vacuum to give 79.2 g (92%) of the 4,6-dimethoxyisatoic anhydride.

Provenance & Evidence