Borane → HCID 59199430, compound

Participants

Reaction Steps

To a solution of 3-(2-methyl-3-oxo-1,2,3,4-tetrahydro-isoquinolin-4-yl)-3H-imidazole-4-carboxylic acid methyl ester (90 mg, 0.316 mmol) in THF (2 mL) is added a 1 M solution of borane in THF (1.6 mL, 1.6 mmol). The reaction is permitted to stir for 1 hour, at which time it is quenched with 1 M aqueous HCl. The acidified reaction is permitted to stir for one hour and then is treated with 1 N aqueous NaOH until the pH is >7. The mixture is then extracted with dichloromethane. The organic extract is dried over Na2SO4, filtered, and concentrated. The resulting residue is purified by semi-preparative reverse phase HPLC (5 to 100% acetonitrile/water w/0.1% NH4OH) to furnish 3-(2-methyl-1,2,3,4-tetrahydro-isoquinolin-4-yl)-3H-imidazole-4-carboxylic acid methyl ester; MS: (ESI) m/z 272.2 (M+H)+. The HCl salt of the title compound can be prepared by dissolution in diethyl ether followed by treatment with an excess of 1N HCl in diethyl ether. The resulting heterogeneous solution is concentrated to furnish the HCl salt of 3-(2-methyl-1,2,3,4-tetrahydro-isoquinolin-4-yl)-3H-imidazole-4-carboxylic acid methyl ester; 1H NMR (400 MHz, CDCl3) δ ppm 2.39 (s, 3 H), 2.80 (dd, J=12.4, 3.8 Hz, 1 H), 2.94-3.02 (m, 1 H), 3.40 (d, J=15.2 Hz, 1 H), 3.91 (s, 3 H), 3.90-3.96 (m, 1 H), 6.35 (m, 1 H), 7.11-7.23 (m, 3 H), 7.24-7.32 (m, 1 H), 7.50 (s, 1 H), 7.77 (s, 1 H).

Provenance & Evidence