Benzyl Bromide → 4-Benzyl-7,7-dimethyl-3-((4-methylbenzyl)sulfonyl)-5-phenyl-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidine

Participants

Reaction Steps

To a solution of 0.34 g (0.86 mmol) of 5 in 10 mL of THF at ° C. was added 0.128 mL (1.07 mmol) of benzyl bromide followed by 0.034 g (0.86 mmol) of sodium hydride (60% dispersion in mineral oil). The reaction was allowed to warm to room temperature after 30 min and stirred for an additional 30 min before being quenched with water. The quenched reaction was diluted with five volumes of water and extracted with AcOEt. The combined organic layers were washed with brine, dried over sodium sulfate, filtered and concentrated in vacuo. The crude product was purified by flash chromatography eluting with 70% hexanes/AcOEt to give 0.39 g (93%) of the title compound as a white solid. 1H NMR (CDCl3) δ 1.27 (s, 3H), 1.52 (s, 3H), 1.93-2.05 (m, 2H), 2.27 (s, 3H), 3.83 (d, J=15.8 Hz, 1H), 4.18-4.30 (m, 3H), 5.51 (d, J=15.8 Hz, 1H), 6.98-7.00 (m, 2H), 7.09 (dd, J=8.2, 12.1 Hz, 4H), 7.17 (d, J=6.8 Hz, 2H), 7.26-7.30 (m, 3H), 7.32-7.40 (m, 3H), 7.47 (s, 1H).

Provenance & Evidence