反应详情

Oxalyl chloride (8.64 mL, 99.0 mmol) and one drop of N,N-dimethylformamide (DMF) were added to a methylene chloride (30 mL) solution of 4-(2-cyclopropylethoxy)benzoic acid (9.28 g, 45.0 mmol) prepared in Example 1 (1a), under ice-cooling. The mixture was stirred at room temperature for 1.75 hours, and then the solvent was evaporated. Then, the obtained residue was suspended in THF (3 mL). This suspension was dropwise added to a 50% THF aqueous solution (120 mL) of glycine (4.41 g, 58.7 mmol) and triethylamine (15.7 mL, 112 mmol) under ice-cooling. The resulting mixture was stirred at room temperature for 1.5 hours, and the solvents (mainly THF) were evaporated. Then, 10% hydrochloric acid (40 mL) was added to the residue under ice-cooling. The resulting precipitate was collected by filtration, washed with water, and dried by heating under reduced pressure to give 11.4 g of the title compound (powder, yield: 97%).

1. temperaturecooling
2. customthe solvent was evaporated
3. temperaturecooling
4. stirringThe resulting mixture was stirred at room temperature for 1.5 hours
5. customthe solvents (mainly THF) were evaporated
6. additionThen, 10% hydrochloric acid (40 mL) was added to the residue under ice-
7. temperaturecooling
8. filtrationThe resulting precipitate was collected by filtration
9. washwashed with water
10. customdried
11. temperatureby heating under reduced pressure