反应详情

To a solution of 10 g (29 mmol) of 4-(2,3-dihydrobenzofuran-7-yl)-2-hydroxy-4-methyl-2-trifluoromethylpentanoic acid ethyl ester in 20 mL of acetic acid (HOAc) was added dropwise a solution of 1.55 mL (30 mmol) of bromine in 10 nL of HOAc. The reaction was monitored by proton NMR. An additional 0.5 mL of Br2 was added. The mixture was diluted with saturated aqueous sodium bicarbonate and extracted with diethyl ether. The organic layer was dried over magnesium sulfate and concentrated in vacuo to afford 11.7 g (95%) of 4-(5-bromo-2,3-dihydrobenzofuran-7-yl)-2-hydroxy-4-methyl-2-trifluoromethylpentanoic acid ethyl ester.

1. extractionextracted with diethyl ether
2. dry with materialThe organic layer was dried over magnesium sulfate
3. concentrationconcentrated in vacuo