反应详情

Water (2 mL) and methanol (8 mL) were added to ethyl 2-(3,3-dimethylbutyrylamino)-4,5,6,7-tetrahydrobenzthiazol-4-carboxylate (185 mg, 0.57 mmol) and NaOH (27 mg, 0.675 mmol), and the resultant mixture was stirred at room temperature under a blanket of nitrogen as inert gas. To complete the reaction, NaOH (200 mg, 5 mmol) was again added, and stirring was continued for a further 24 hours at room temperature. Following removal of MeOH, 2M HCl (10 mL) was added, and the resultant mixture was extracted with CH2Cl2 (3×20 mL). Following drying of the combined organic phases over Na2SO4 and filtration, there was obtained the product 2-(3,3-dimethylbutyrylamino)-4,5,6,7-tetrahydrobenzthiazol-4-carboxylic acid in a yield of 144 mg (corresponding to 85% of theory).

1. additionwas again added
2. customremoval of MeOH, 2M HCl (10 mL)
3. additionwas added
4. extractionthe resultant mixture was extracted with CH2Cl2 (3×20 mL)
5. dry with materialFollowing drying of the combined organic phases over Na2SO4 and filtration