Methanol → 7-Butyl-3-hydroxy-2-(3,4,5-trihydroxy-phenyl)-chromen-4-one

Participants

Reaction Steps

To a stirring solution of 39d (0.389 g, 1 mmol) in dichloromethane (15 ml) under Ar was added boron tribromide in dichloromethane (1.0M, 5.0 ml, 5 mmol, 4.9 equ). The mixture was then stirred for 18 hours. Methanol (5 ml) was then added. The reaction was heated to reflux for 2 hours, then concentrated in vacuo to give a brown solid. Water (25 ml) was added and the mixture sonicated then extracted into ethyl acetate (3×). The organic layer was washed with brine then dried (MgSO4) and concentrated in vacuo to give 9d (0.302 g, 77%) as a brown solid.

Provenance & Evidence