HCID 59490386, compound → HCID 59490386, compound

Participants

Reaction Steps

A solution of tert-butyl 3-(4-methoxybenzyl)-6,7,8,9-tetrahydro-3H-pyrazolo[3,4-c]isoquinolin-7-ylcarbamate (0.200 g, 0.49 mmol) in trifluoroacetic acid (2 mL) was heated at 65° C. for 16 hours. LC-Mass analysis of the reaction indicated the formation of both N-tert-butyl-3-(4-methoxybenzyl)-6,7,8,9-tetrahydro-3H-pyrazolo[3,4-c]isoquinolin-7-amine (LCMS [M+H]: 245, 45%, UV) and 3-(4-methoxy-benzyl)-6,7,8,9-tetrahydro-3H-pyrazolo[3,4-c]isoquinolin-7-ylamine (LCMS [M+H]: 189, 42%, UV). The reaction mixture was concentrated and then partitioned between dichloromethane (50 mL) and aqueous NaHCO3 (50 mL). The organic layer was separated, washed with brine (30 mL), dried (Na2SO4), filtered and concentrated under reduced pressure. The crude product was purified using flash column chromatography (SiO2, 90% dichloromethane/10% methanol/3% ammonia) to give the pure desired product, N-tert-butyl-[3-(4-methoxy-benzyl)-6,7,8,9-tetrahydro-3H-pyrazolo[3,4-c]isoquinolin-7-yl]-amine as a pale yellow solid (0.015 g, 12%). M.p.=>58° C.; 400 MHz 1H NMR (DMSO-d6) δ: 8.31 (s, 1H), 7.76 (s, 1H), 3.4-3.2 (br s, 1H), 3.15-2.94 (m, 3H), 2.93-2.82 (m, 1H), 2.6-2.52 (m, 1H), 2.05-1.8 (m, 2H), 1.65 (s, 9H); LCMS [M+H]: 245.

Provenance & Evidence