Cesium carbonate → 1,3-Dibromo-5-monofluoromethoxybenzene

Participants

Reaction Steps

To a tared, sealed 350 mL round-bottomed pressure flask containing a suspension of 3,5-dibromophenol (10.0 g, 39.7 mmol; see step (ii) above) and Cs2CO3 (20.7 g, 63.5 mmol) in DMF (150 mL) at −78° C. was added chlorofluoromethane via bubbling for 5 min through the septum. The septum was replaced with a Teflon stopper and the flask was then sealed and allowed to warm to room temperature where the flask was weighed and determined to contain 9.0 g (131 mmol) of chlorofluoromethane. The solution was heated in an oil bath set at 70° C. overnight. The flask was cooled to room temperature, the pressure cautiously released and the contents diluted with water (100 mL). The aqueous layer was extracted with Et2O (3× 200 mL) then, the combined organics were dried (Na2SO4), filtered and concentrated in vacuo. Flash chromatography on silica gel eluting with hexanes afforded the sub-title compound (7.9 g, 71%) as a white solid.

Provenance & Evidence