反应详情

温度

80 °C

A mixture of 5-bromo-4-chloro-2-hydroxy-benzoic acid (5 g, 19.9 mmol), 4-bromo-butyric acid tert-butyl ester (13.2 g, 59.7 mmol) and K2CO3 (11.1 g, 79.6 mmol) in DMF (100 mL) was heated at 80° C. for 2 days. The solid was filtered off. The solution was concentrated and purified via silica gel flash chromatography (eluting with 20% ethyl acetate in hexane) to give 5-bromo-2-(3-tert-butoxycarbonyl-propoxy)-4-chloro-benzoic acid 3-tert-butoxycarbonyl-propyl ester (8.2 g). MS [M-iso-butene+H]+: 480.9; tR=3.32 min. (method 1)

1. filtrationThe solid was filtered off
2. concentrationThe solution was concentrated
3. custompurified via silica gel flash chromatography (eluting with 20% ethyl acetate in hexane)