Hydrochloric Acid → 6-(Methyloxy)-2-[3-(4-morpholinyl)propanoyl]-1,2,3,4-tetrahydro-7-isoquinolinamine

Participants

Reaction Steps

6-(methyloxy)-2-[3-(4-morpholinyl)propanoyl]-7-nitro-1,2,3,4-tetrahydroisoquinoline (assumed 1.62 mmol from previous reaction) was dissolved in dimethylformamide (3.0 mL) and diluted with ethanol (10 mL). The solution was treated with tin (II) chloride dihydrate (2.2 g, 9.6 mmol, Aldrich), hydrochloric acid (1.0 mL, 1.0 mmol, 1 M in water), and stirred for 16 h. Excess saturated aqueous sodium bicarbonate was added carefully and the observed white suspension was stirred for 1 h. The mixture was filtered through celite. The filtrate was concentrated and purified by chromatography on SiO2 (dichloromethane to 20% methanol/dichloromethane) to give 6-(methyloxy)-2-[3-(4-morpholinyl)propanoyl]-1,2,3,4-tetrahydro-7-isoquinolinamine (350 mg, 1.10 mmol, 68% over two steps) which was slightly contaminated with DMF. 1H NMR (400 MHz, DMSO-d6) is complicated by amide rotomers d ppm 2.31-2.41 (m, 4 H), 2.52-2.71 (m, 6 H), 3.50-3.57 (m, 4 H), 3.57-3.62 (m, 2 H), 3.72 (s, 3 H), 4.37-4.47 (two singlets at 4.38 and 4.45, 2 H), 4.54-4.61 (two broad singlets at 4.56 and 4.59, 2 H), 6.38-6.41 (two singlets at 6.39 and 6.40, 1 H), 6.55-6.58 (two singlets at 6.56 and 6.57, 1 H); ESIMS (M+H)+=320.

Provenance & Evidence