Methanol → HCID 86644973, compound

Participants

Reaction Steps

6-Benzyloxy-4-ethoxy-7-methoxy-3,4-dihydro-1H-isoquinoline-2-carboxylic acid tert-butyl ester (4.7 g, 11.4 mmol) was stirred in THF (50 mL) and methanol (5 mL) and cooled to 0° C. before acetyl chloride (2 mL, 28 mmol) was added drop wise. The solution was stirred at rt for an o/n. After addition of DCM (100 mL) the organic layer was washed with a solution of saturated aqueous NaHCO3, water, brine, dried (MgSO4), filtered and concentrated to afford 3.6 g of crude product. Column chromatography (petroleum ether/ethyl acetate 9/1 to 0/1 then ethyl acetate/methanol 1/0 to 10/1) afford 1.5 g (42%) of 6-Benzyloxy-4-ethoxy-7-methoxy-1,2,3,4-tetrahydroisoquinoline F15 and 6-benzyloxy-7-methoxyisoquinoline F16 (0.7 g, 23%). F15 white powder, m.p. 55-56° C., 1H NMR (270 MHz, CDCl3) δ 1.16 (3H, t, J=6.9 Hz), 2.10 (1H, br), 2.91 (1H, dd, J=13.8 and 2.8 Hz), 3.29 (1H, dd, J=13.8 and 2.5 Hz), 3.37-3.61 (2H, m), 3.84 (3H, s), 3.87-3.95 (2H, m), 4.00-4.06 (1H, m), 5.14 (2H, s), 6.53 (1H, s), 6.78 (1H, s), 7.26-7.44 (5H, m). HRMS (ES) calcd. for C19H24NO3 (MH+), 314.1751 found 314.1744. HPLC: tr=4.16 (95.8%) CH3CN/H2O 90/10.

Provenance & Evidence