Cesium carbonate → 2-(5-chloro-2-nitrophenylamino)-6-(pyridin-4-yl)-9-(tetrahydro-2H-pyran-4-yl)-7H-purin-8(9H)-one

Participants

Reaction Conditions

Reaction Steps

To an oven-dried vial was added 2-amino-6-(pyridin-4-yl)-9-(tetrahydro-2H-pyran-4-yl)-7H-purin-8(9H)-one (68 mg, 0.22 mmol, 1 equiv.) in anhydrous toluene (1 mL), then freshly grounded cesium carbonate (99.4 mg, 0.31 mmol, 1.4 equiv.) with stirring at room temperature under Ar. After 20 min, Pd(OAc)2 (15 mg, 0.02 mmol, 0.1 equiv.), racemic BINAP (20.5 mg, 0.03 mmol, 0.15 equiv.) and 1-bromo-5-chloro-2-nitrobenzene (WO 02/053545 A1) (67.6 mg, 0.29 mmol, 1.3 equiv.) were added as solids, followed by anhydrous DMSO (1 mL). The vial was purged with Ar for 3 min, then closed and heated in a microwave oven at 170° C. for 45 min. The reaction mixture was cooled to room temperature, diluted with ethyl acetate/methylene chloride, filtered through a Nylon 0.45 μm filter, and the filtrate was concentrated in vacuo. The resulting residue was purified using preparative TLC (silica gel, 7.5% methanol in methylene chloride) to give the desired product as a brown solid (11 mg, 11% yield). 1H NMR (300 MHz, CDCl3+CD3OD) δ, ppm: 9.13 (s, 1H), 8.63 (br m, 2H), 8.13 (d, J=8.9 Hz, 1H), 7.83 (br m, 2H), 6.91 (d, J=8.6 Hz, 1H), 4.70-4.50 (m, 1H), 4.10-4.03 (m, 2H), 3.51-3.43 (m, 2H), 2.68-2.65 (m, 2H), 1.71-1.66 (m, 2H); MS (EI) m/z 468.4 (MH)+.

Provenance & Evidence