HCID 71086630, compound → HCID 71086819, compound

Participants

Reaction Conditions

Reaction Steps

To a 20 L round-bottomed flask was charged nitrogen and palladium on carbon (10% Pd/C) (100 g, 60% wet paste) and ethanol (12 L), followed by the addition of [(3,5-bis-benzyloxypyridine-2-carbonyl)-amino]-acetic acid ethyl ester, 1, (1000 g, 2.378 mol). The resulting mixture was subjected to a vacuum-nitrogen purge cycle three times and a vacuum-hydrogen purge cycle three times. A hydrogen atmosphere was introduced and the reaction mixture was stirred at 1-25° C. until the completion of the reaction by TLC analysis. The reaction typically lasted 2 to 3 hours and a vigorous stirring was important to complete the reaction. The reaction system was then subjected to a vacuum-nitrogen purge cycle to remove hydrogen from the system. The reaction mixture was filtered and the filter-cake was washed with ethanol (2 L). The combined filtrate was concentrated on a rotary evaporator at up to 45° C. bath temperature to a constant weight to provide 558 g (97.7% yield) of the desired product as an off-white solid. MP: 138-140° C.; MS (ESI+): m/z 241 (M+1); 1H NMR (300 MHz, DMSO-d6) δ 12.28 (s, 1H), 10.79 (s, 1H), 9.09-9.05 (t, J=6 Hz, 1H), 7.76-7.71 (d, J=2.4 Hz, 1H), 6.68-6.67 (d, J=2.1 Hz, 1H), 4.15-4.08 (q, J=6.9 Hz, 2H), 4.02-4.00 (d, J=6.3 Hz, 2H), 1.22-1.17 (t, J=6.9 Hz, 2H).

Provenance & Evidence