Ethanol → 4-(5-Amino-1-benzenesulfonyl 1H-pyrrolo[2,3-b]pyridine-4-ylamino)-piperidine-1-carboxylic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

A suspension of 4-(1-benzenesulfonyl-5-nitro-1H-pyrrolo[2,3-b]pyridin-4-ylamino)-piperidine-1-carboxylic acid tert-butyl ester (11.2 g, 22.4 mmol) and palladium on carbon (1.45 g, 10%, wet, Degussa, E101 NE/W) in a 2:1 mixture of THF and ethanol (150 ml) was stirred under a hydrogen atmosphere (2-3 balloons) at 50° C. for 18 h. The reaction mixture was cooled to 25° C. then was filtered through Celite. The filtrate was concentrated under reduced pressure and the red-orange residue was purified by column chromatography on silica gel (gradient: 0 to 7% CH3OH in CH2Cl2) to give a dark red oil. This material was dissolved in CH2Cl2 (40 ml) and Et2O (200 ml) was added. Concentration of this mixture to approximately 60 ml volume under reduced pressure afforded a pink solid. This material was collected by vacuum filtration, was washed with Et2O (2×30 ml), and was air-dried to afford 4-(5-amino-1-benzenesulfonyl-1H-pyrrolo[2,3-b]pyridin-4-ylamino)-piperidine-1-carboxylic acid tert-butyl ester (7.23 g, 69%). LCMS (Method G, ESI): RT=0.87 min, m+H=472.3; 1H NMR (400 MHz, DMSO) δ 8.04-7.99 (m, 2H), 7.70-7.65 (m, 1H), 7.61-7.55 (m, 3H), 7.49 (d, J=4.2 Hz, 1H), 6.78 (d, J=4.3 Hz, 1H), 5.11 (d, J=8.7 Hz, 1H), 4.37 (s, 1H), 3.94-3.86 (m, 2H), 2.95 (s, 1H), 2.54-2.48 (m, 2H), 1.92-1.79 (m, 3H), 1.40 (s, 9H), 1.38-1.27 (m, 2H).

Provenance & Evidence