Ethanol → Tert-butyl 1-(3-(2-amino-6-fluoropyrazolo[1,5-a]pyrimidine-3-carboxamido)-5-fluoropyridin-4-yl)piperidine-4-carboxylate

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Reaction Conditions

Reaction Steps

6-chloro-1H-benzo[d][1,2,3]triazol-1-yl 2-amino-6-fluoropyrazolo[1,5-a]pyrimidine-3-carboxylate 6a* (45 g, 129.4 mmol) and tert-butyl 1-(3-amino-5-fluoropyridin-4-yl)piperidine-4-carboxylate 27 (40.1 g, 135.9 mmol) were slurried in pyridine (675 ml). The mixture was heated at 95° C. under nitrogen until the reaction was complete (determined by HPLC analysis). The mixture was cooled and ethanol (450 ml) was added dropwise. The mixture was filtered and the filter cake washed with ethanol (2×70 ml). The damp cake was dried to give the product 28 as a yellow crystalline solid (47.7 g, 78%); 1H NMR (500 MHz, DMSO-d6) δ 10.45 (s, 1H), 9.58 (s, 1H), 9.51 (dd, 1H), 8.72 (dd, 1H), 8.25 (d, 1H), 6.81 (s, 2H), 3.15-2.93 (m, 4H), 2.55-2.47 (masked signal, 1H), 2.02-1.91 (m, 4H), 1.47 (s, 9H); 19F NMR (500 MHz, DMSO-d6) δ −153.5, −136.3; MS (ES+) 474.2.

Provenance & Evidence