反应详情

A portion of carboxylic acid 1-D (0.67 g, 1.77 mmol) was suspended in methylene chloride (15 ml) and treated with 1,1′-carbonyldiimidazole (0.57 g, 3.52 mmol) at room temperature and under a nitrogen atmosphere. After 2 h, concentrated ammonium hydroxide was added (40 ml) and the reaction was stirred for 18 h. The crude mixture was diluted with water (150 ml) and extracted with 3 portions of methylene chloride (70 ml). The organic washes were combined, washed with brine, dried (Na2SO4), and stripped to yield 1-E as a white powder. MS (ESI+)=379.3 (M+1); 1H NMR (500 MHz, CDCl3): δ 7.88-7.86 (m, 1 H), 7.75-7.71 (m, 2 H), 7.54 (t, 1 H), 5.75 (s, 1 H), 5.47 (s, 1 H), 3.50 (s, 3 H), 2.22 (t, 6 H), 2.00 (t, 6 H) ppm.

1. extractionextracted with 3 portions of methylene chloride (70 ml)
2. washwashed with brine
3. dry with materialdried (Na2SO4)