Acetyl chloride → (R)-Methyl 5-bromo-1,2,3,4-tetrahydroisoquinoline-3-carboxylate hydrochloride

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Reaction Steps

Dissolve dimethyl (3R)-5-bromo-3,4-dihydro-1H-isoquinoline-2,3-dicarboxylate (27.55 g, 84.0 mmol) in 5N hydrochloric acid (330.6 mL, 1.65 mol) and heat to reflux for three days. Concentrate under reduced pressure to give a white solid. Wash the solid with diethyl ether and dry under vacuum at 40° C. overnight to give (3R)-5-bromo-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid hydrochloride (1:1) (20.8 g, 71.1 mmol). Add acetyl chloride (50.6 mL, 711.0 mmol) to a 0° C. mixture of (3R)-5-bromo-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid hydrochloride (1:1) (20.8 g, 71.1 mmol) in methanol (474 mL). Warm to room temperature and stir for 36 hours. Concentrate under reduced pressure and dry to give the title compound (21.9 g, 71.4 mmol). MS (m/z): 270 (M+1).

Provenance & Evidence