Acetic Acid → 2-Methyl-7-nitro-1,2,3,4-tetrahydroisoquinoline

Participants

Reaction Conditions

Reaction Steps

Into a 125 mL Erlenmeyer flask was charged 7-nitro-1,2,3,4-tetrahydroisoquinoline, hydrochloric acid (3.17 g, 14.77 mmol) in dichloroethane (148 ml). The solution was stirred 10 minutes with 1 N NaOH, and the layers were separated. Paraformaldehyde (2.217 g, 73.8 mmol), acetic acid (4.23 ml, 73.8 mmol) and sodium cyanoborohydride (4.64 g, 73.8 mmol) were added. The reaction was heated at 90° C. overnight. The reaction was cooled to room temperature, and quenched with saturated aqueous sodium bicarbonate. The layers were separated, and the organic layer was dried over MgSO4, filtered, and concentrated onto silica gel. The reaction was purified by flash chromatography (50% ethyl acetate:hexanes for 20 minutes, then to 100% ethyl acetate:hexanes over 30 minutes) to provide the title compound. MS (DCI) m/e 193 (M+H)+.

Provenance & Evidence