Benzaldehyde → 6-Bromoflavanone

Participants

Reaction Steps

A mixture of 1-(5-bromo-2-hydroxy-phenyl)-ethanone (29 g, 0.135 mol), benzaldehyde (14.3 g, 0.135 mol) and borax (51.5 g, 0.135 mol) in ethanol (180 mL) and H2O (300 mL) was refluxed for one day. The reaction mixture was cooled, diluted with an equal volume of H2O and extracted with ethyl acetate. The organic layer was dried over anhydrous Na2SO4, filtered, and evaporated to give 6-bromo-2-phenyl-chroman-4-one (8.5 g, 21%). 1H-NMR (CDCl3): 2.89 (dd, 1H), 3.06 (dd, 1H), 5.46 (dd, 1H), 6.95 (d, 1H), 7.37-7.46 (m, 5H), 7.58 (d, 1H), 8.02 (d, 1H).

Provenance & Evidence