Hexamethylphosphorous triamide → 2-(4-Bromo-1H-pyrazolo[3,4-d]pyrimidin-1-yl)-1-phenylethanol

Participants

Reaction Steps

To a cold (−20° C.) suspension of 10 (2.56 g, 10 mmol) and NBS (7.12 g, 40 mmol) in dry acetonitrile (20 mL), hexamethylphosphorous triamide (HT) (6.53 g, 40 mmol) was added dropwise. After addition, the cold bath was removed and the reaction mixture stirred at room temperature for 0.5 h. LiBr (3.44 g, 40 mmol) was added and the mixture was heated at 70° C. for 5 h. The mixture was evaporated under reduced pressure. The dark oil was purified by column chromatography (Silica Gel, 100 Mesh) using CHCl3 as the eluant, to afford the pure product 11 (1.40 g, 44%) as a white solid: mp 146-147° C. 1H NMR: δ 3.46-3.53 (br s, 1H, OH, disappears with D2O), 4.57-4.79 (m, 2H, CH2N), 5.18-5.29 (m, 1H, CHO), 7.30-7.52 (m, 5H Ar), 8.01 (s, 1H, H-3), 8.48 (s, 1H, H-6). IR cm−1: 3240-2500 (OH). Anal. (C13H11N4OBr) C, H, N.

Provenance & Evidence