Acetaldehyde → HCID 67979996, compound

Participants

Reaction Steps

A solution of methyl 2-{[1-(tert-butoxycarbonyl)-4-methylpiperidin-4-yl]carbonyl}-1,2,3,4-tetrahydroisoquinoline-6-carboxylate.[HCl] (0.260 g, 0.737 mmol) in MeOH (8.0 mL) was treated with acetaldehyde (0.414 g, 7.37 mmol) and MgSO4 (excess). The reaction mixture was stirred at rt for 1 h, and sodium cyanoborohydride (93 mg, 1.47 mmol) was added in portions. The resulting mixture was stirred for 3 h at rt and then filtered to remove the MgSO4. The filtrate was washed with water and brine, dried over Na2SO4, filtered and concentrated. The resulting residue was purified by column chromatography (SiO2, 0-20% MeOH in DCM) to give methyl 2-[(1-ethyl-4-methylpiperidin-4-yl)carbonyl]-1,2,3,4-tetrahydroisoquinoline-6-carboxylate (55 mg, 22%). LC-MS: (FA) ES+ 345; 1H NMR (400 MHz, CDCl3) δ 7.86-7.80 (m, 2H), 7.18 (d, J=7.9 Hz, 1H), 4.78 (s, 2H), 3.89 (s, 3H), 3.88-3.83 (m, 2H), 2.91 (t, J=5.5 Hz, 2H), 2.77-2.67 (m, 2H), 2.42 (q, J=7.2 Hz, 2H), 2.36-2.20 (m, 4H), 1.75-1.65 (m, 2H), 1.30 (s, 3H), 1.09 (t, J=7.2 Hz, 3H).

Provenance & Evidence