Cesium carbonate → tert-butyl 3-(6-((diphenylmethylene)amino)-1H-imidazo[4,5-c]pyridin-1-yl)piperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of tert-butyl 3-(6-bromo-1H-imidazo[4,5-c]pyridin-1-yl)piperidine-1-carboxylate (0.6 g, 1.58 mmol, 1.0 eq) in DMA (5 mL) were added Ph2NH (430 mg, 2.37 mmol, 1.5 eq), Pd3(dba)2 (87 mg, 0.095 mmol, 0.06 eq), Xantphos (91 mg, 0.16 mmol, 0.1 eq) and Cs2CO3 (0.8 g, 2.5 mmol, 1.6 eq) at rt under N2. The mixture was stirred at 115° C. for 16 h, cooled to rt and the solid was filtered off and washed with EtOAc (30 mL). The organic layer was washed with H2O (20 mL×2) and brine (10 mL), separated, dried (Na2SO4) and concentration in vacuo to afford a residue which was purified by silica gel column chromatography with EtOAc in PE (1/1 v/v) to give the title compound (0.4 g, 50%) as brown solid. 1H NMR (400 MHz, CDCl3) δ: 8.80 (s, 1H), 7.89 (s, 1H), 7.82 (d, 2H), 7.52-7.48 (m, 1H), 7.44-7.40 (m, 2H), 7.27-7.24 (m, 3H), 7.24-7.17 (m, 2H), 6.68 (s, 1H), 4.13-4.09 (m, 2H), 3.95-3.92 (m, 1H), 3.18-3.14 (m, 1H), 3.01-2.94 (m, 1H), 1.95-1.90 (m, 2H), 1.79-1.76 (m, 1H), 1.63-1.60 (m, 1H), 1.53 (s, 9H). ESI-MS (M+H+): 382.0.

Provenance & Evidence