反应详情

A mixture of 2.25 g (18.6 mmol) of 5-hydroxycoumarin, 4.2 g (20 mmol) of ethyl 5-bromovalerate, 7.0 g (50 mmol) of anhydrous, granular potassium carbonate, and 10 mL of dimethyl sulfoxide was stirred at room temperature for 24 hr. The resulting slurry was filtered with suction and the solids washed well with ethyl acetate. The filtrate and washes were combined and poured into water and the mixture was worked-up with ethyl acetate in the usual manner. The semi-solid residue was triturated and washed with hexane giving 2.36 g (44%) of 5-[(2-oxo-2H-1-benzopyran-5-yl)oxy]pentanoic acid ethyl ester as a tan solid.

1. filtrationThe resulting slurry was filtered with suction
2. washthe solids washed well with ethyl acetate
3. additionpoured into water
4. customThe semi-solid residue was triturated
5. washwashed with hexane giving 2.36 g (44%) of 5-[(2-oxo-2H-1-benzopyran-5-yl)oxy]pentanoic acid ethyl ester as a tan solid