2,7-Naphthalenediol → 7-Bromo-2-naphthol

Participants

Reaction Conditions

Reaction Steps

Triphenyl phosphine (89.7 g, 0.342 mol) and acetonitrile (350 mL) were combined in a 1-L flask under N2 atmosphere. The mixture was cooled to 10° C. Bromine (17.6 mL, 0.342 mol) was added dropwise over 10 minutes. The cooling bath was removed and 2,7-dihydroxynaphthalene (50.0 g, 0.312 mol) was added along with 350 mL of CH3CN rinse. The resulting yellow tan mixture was heated at reflux for 3 hours. Acetonitrile was distilled off using a water aspirator over 2 hours resulting in a grayish white solid. The solid was heated to 280° C. over 30 minutes giving a black liquid. The liquid was heated to 310° C. over 20 minutes and the temperature was maintained at 310° C. for an additional 15 minutes until gas evolution ceased. The black mixture was cooled to room temperature. Chromatography yielded 34.5 g of the intermediate title compound as an off-white solid which was 87% pure by HPLC (43% yield).

Provenance & Evidence