反应详情

To a solution of 3′-amino-2′-methoxybiphenyl-3-carboxylic acid (5 g) prepared as in Example 6, in hydrochloric acid (8.5 mL) and methanol (90 mL) was added a solution of sodium nitrite (1.41 g in 400 mL of water) at about 0° C. to about 5° C. under stirring. The reaction mixture was stirred for about 15 minutes at about 5° C. Then ethyl acetoacetate (2.7 g) was added and the reaction mixture was stirred for about 15 minutes at about 0° C. to about 5° C. Solid sodium bicarbonate (15 g) and ethanol (30 mL) was added and the reaction mixture was allowed to warm to about room temperature and stirred for about 2 hours. The mixture was filtered, washed with water (50 mL) and dried under vacuum at about 35° C. to about 40° C. for about 6 hours.

1. stirringThe reaction mixture was stirred for about 15 minutes at about 5° C
2. stirringthe reaction mixture was stirred for about 15 minutes at about 0° C. to about 5° C
3. temperatureto warm to about room temperature
4. stirringstirred for about 2 hours
5. filtrationThe mixture was filtered
6. washwashed with water (50 mL)
7. customdried under vacuum at about 35° C. to about 40° C. for about 6 hours