反应详情

2,5-Dimethoxy-3,4,6-trimethylbenzoic acid (m.p. 98°-100° C. was reacted with methyl 3-amino-4-hydroxyphenylacetate to give methyl 4-hydroxy-3-(2,5-dimethoxy-3,4,6-trimethylbenzoylamino)phenylacetate [m.p. 159°-160° C., δ 2.14 (3H), 2.20 (3H), 2.32 (3H), 3.48 (2H), 3.65 (6H), 3.70 (3H), 7.02 (3H), 8.30 (1H), 8.87 (1H)] (11.0 g, 28.4 mmol), which was dehydrated with phosphorus oxychloride (13.1 g) to give methyl 2-[6-(2,5-dimethoxy-3,4,6-trimethylphenyl)benzoxazol-6-yl]acetate m.p. 68°-69° C., δ 2.22 (3H), 2.27 (3H), 3.58 (3H), 3.70(3H), 3.72 (3H), 3.76 (2H), 7.32 (1H), 7.55 (1H), 7.76 (1H)] .