反应详情

Into the solution of 1,3-cycloheptanedione (252 mg, 2.0 mmol) in 5 mL of CH2Cl2 was added a solution of Br2 (320 mg, 2.0 mmol) in 2 mL of CH2Cl2. The mixture was stirred at room temperature for 15 minutes. The white solid was collected, washed with CH2Cl2, and dried to give 2-bromo-1,3-cycloheptanedione (330 mg), which was used for next step with no further purification. Into the solution of 2-bromo-1,3-cycloheptanedione (205 mg, 1 mmol) in 5 mL of MeOH was added thiourea (152 mg, 2 mmol) and K2CO3 (276 mg, 2 mmol). The mixture was stirred at 70° C. for 1 hour, cooled down to room temperature. The solution was concentrated, and the residue was partitioned between EtOAc and H2O. The aqueous layer was washed with EtOAc. The combined organic phases were dried (Na2SO4) and concentrated to give the crude thiazole 22a as a yellow solid.

1. customThe white solid was collected
2. washwashed with CH2Cl2
3. customdried