Cesium carbonate → tert-Butyl 9-[1-(4-amino-3-methyl-1H-pyrazolo[3,4-d]pyrimidin-1-yl)ethyl]-7-chloro-6-methyl-2,3-dihydro-1,4-benzoxazepine-4(5H)-carboxylate

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Reaction Steps

Cesium carbonate (500 mg, 2 mmol) was added to a mixture of 3-methyl-1H-pyrazolo[3,4-d]pyrimidin-4-amine (150 mg, 0.98 mmol) in N,N-dimethylformamide (30 mL) and stirred for 10 minutes. To this was added tert-butyl 7-chloro-9-(1-chloroethyl)-6-methyl-2,3-dihydro-1,4-benzoxazepine-4(5H)-carboxylate (290 mg, 0.82 mmol) in N,N-dimethylformamide (1 mL) and the reaction was stirred at 80° C. for 1 hour. The mixture was diluted with ethyl acetate and washed with water and brine. The extracts were dried over sodium sulfate, filtered and evaporated. The crude was dissolved in methylene chloride and filtered to remove insoluble material (unwanted regioisomer). Purification on silica gel using ethyl acetate in hexanes (0-100%) followed by methanol in ethyl acetate (0-15%) gave the desired compound (240 mg, 62%). LCMS calculated for C23H30ClN6O3(M+H)+: m/z=473.2; found: 473.2. 1H NMR (300 MHz, CD3OD): δ 8.14 (s, 1 H), 7.29 (m, 1 H), 6.32 (m, 1 H), 4.70 (m, 1 H), 4.40 (m, 1 H), 3.83 (m, 2 H), 3.57 (m, 2 H), 2.58 (s, 3 H), 2.48 (m, 3 H), 1.78 (m, 3 H), 1.39 (, 9H).

Provenance & Evidence