Potassium Carbonate → 4-[2-Chloro-5-(5-isopropyl-2-methyl-phenoxymethyl)-6-methyl-pyrimidin-4-yl]-piperazine-1-carboxylic acid tert-butyl ester

Beteiligte Stoffe

Reaktionsschritte

To a solution of 2,4-dichloro-5-(5-isopropyl-2-methyl-phenoxymethyl)-6-methyl-pyrimidine (978 mg, 3.01 mmol) in DMA (4 mL) is added piperazine-1-carboxylic acid tert-butyl ester (560 mg, 3.01 mmol) and potassium carbonate (832 mg, 6.02 mmol). The resulting colorless suspension is stirred at room temperature under nitrogen for 16 h. The reaction mixture is partitioned between EtOAc (60 mL) and water (20 mL), the organic layer is separated, washed with water (20 mL×2), brine (20 mL), dried over sodium sulfate, filtered and evaporated at reduced pressure to obtain a colorless oil consisting of a ˜2:1 mixture of isomeric addition products. Purification on a 30 g cartridge of silica gel (10-30% EtOAc/Hexanes) affords the title compound (lower Rf material) as a colorless solid foam. 1H NMR (CDCl3) δ=7.11 (d, 1H), 6.83 (d, 1H), 6.75 (s, 1H), 4.84 (s, 2H), 3.52 (m, 8H), 2.90 (m, 1H), 2.47, (s, 3H), 2.16, (s, 3H), 1.45, (s, 9H), 1.27 (d, 6H).

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