Trimethyl borate → HCID 178454343, compound

Participants

Reaction Conditions

Reaction Steps

To a cooled (−78° C.) solution of di-tert-butyl{4-[1-(trans-4-{[tert-butyl(dimethyl)silyl]oxy}cyclohexyl)-1H-pyrazol-4-yl]furo[2,3-c]pyridin-7-yl}imidodicarbonate (1 g, 2 mmol) in anhydrous THF (10 mL) was added lithium diisopropylamide (2 M in THF, 1.47 mL, 2.94 mmol), and the mixture stirred for 30 min. Boric acid, trimethyl ester (0.371 mL, 3.26 mmol) was added, and the mixture stirred for 10 min before warming to 0° C. The mixture was quenched with water (0.2 mL) and warmed to RT. The THF was removed by rotary evaporation, and the residue was partitioned between ethyl acetate and water. Following separation of the layers, the organic layer was dried over sodium sulfate and evaporated. To the resulting foam was added heptane, and the solution was stirred until the particles were reduced to a powdery solid. The mixture was filtered and washed with heptane (10×). The solid was dried under vacuum to afford 0.6 g (60%) of the title compound as a beige solid. 1H NMR (400 MHz, CD3OD): δ 8.23 (s, 1 H), 8.22 (s, 1 H), 8.01 (s, 1 H), 7.07 (s, 1 H), 4.39-4.18 (m, 1 H), 3.93-3.70 (m, 1 H), 2.26-2.13 (m, 2 H), 2.11-1.92 (m, 4 H), 1.60-1.53 (m, 2 H), 1.33 (s, 18 H), 0.93 (s, 9 H), 0.12 (s, 6 H).

Provenance & Evidence