反应详情

0.415 g (1.10 mmol) of 2,4-dibromo-3-(ethylcarbonylmethoxy)benzoic acid, 0.140 g (1.20 mmol) of cyclohexane-1,3-dione, 0.222 g (1.10 mmol) of N′-(3-dimethylaminopropyl)-N-ethylcarbodiimide hydrochloride and 0.001 g of dimethylaminopyridine were stirred in 30 ml of CH2Cl2 at room temperature for 3 h. The mixture was then diluted with CH2Cl2 and washed with 0.5 N HCl, with water, with saturated NaHCO3 solution and again with water. The combined organic phases were dried over Na2SO4 and evaporated to dryness, giving 3-oxo-1-cyclohexenyl 2,4-dibromo-3-(ethylcarbonylmethoxy)benzoate in the form of a yellow resin which was sufficiently pure for the subsequent reaction.

1. washwashed with 0.5 N HCl, with water, with saturated NaHCO3 solution and again with water
2. dry with materialThe combined organic phases were dried over Na2SO4
3. customevaporated to dryness