Water → 2',3,3',4,4',5-Hexamethoxybenzophenone

Participants

Reaction Steps

To a solution of bromobenzene 9 (0.21 g) in dry tetrahydrofuran (5 mL) cooled to −78° C. was added n-butyl lithium (0.38 mL, 2.5 M, 1.1 eq.). The solution was stirred for 30 min. and 3,4,5-trimethoxybenzoyl chloride (0.2 g) in anhydrous tetrahydrofuran was added. The resulting solution was then stirred for an additional 28 hours. The reaction was stopped with water, extracted with ethyl acetate and the solvent removed (in vacuo) to give a yellow oil. Separation by flash column chromatography (hexane-ethyl acetate, 3:1) afforded a colorless solid (0.06 g, 20.5%). The solid was recrystallized twice from ethyl acetate-hexane: m.p. 124.6-125.9° C., lit22 m.p. 121° C.; EIMS m/z 362 (M+), 345, 317, 181, 169, 151; 1H NMR δ 7.11 (1H, d, J=9.0 Hz, H6), 7.08 (2H, s, H2,6), 6.72 (1H, d, J=9.0 Hz, H5′), 3.94 (3H, s, OCH3), 3.93 (3H, s, OCH3), 3.90 (3H, s, OCH3), 3.85 (6H, s, OCH3,3,5), 3.80 (3H, s, OCH3).

Provenance & Evidence