Tetrahydrofuran → HCID 11232950, compound

Participants

Reaction Conditions

Reaction Steps

The product from Example 144 (167 mg, 0.48 mmol) was dissolved into 1 M BH3 in tetrahydrofuran (2 mL, 2 mmol), stirred at room temperature overnight, quenched with 0.5 M aqueous dipotassium hydrogen phosphate, and diluted with EtOAc. The organic phase was separated and washed consecutively with 0.5 M aqueous dipotassium hydrogen phosphate and brine, dried (Na2SO4), concentrated, and chromatographed through a short column of silica with a gradient of 0 to 5% MeOH/CH2Cl2, and through a second short column of silica with a gradient of 0 to 5% MeCN/CH2Cl2, collecting and concentrating the material with a mass ion corresponding to a borane complex. This residue was dissolved in methanol (1.5 mL), treated with 0.1 M aqueous hydrochloric acid (0.3 mL), heated at 60° C. for three hours, treated with more 0.1 M aqueous hydrochloric acid (0.1 mL), heated at 60° C. for one hour, concentrated, and chromatographed through a short column of silica with a gradient of 2 to 10% 2 M NH3 in MeOH/CH2Cl2 to provide the title compound as a white powder (13% yield). MS (ESI APCI) m/z 336 (M+H)+; 1HNMR (300 MHz, CD3OD) δ 1.18 (s, 3H), 1.38-1.53 (m, 1H), 1.73-1.87 (m, 2H), 1.94-2.08 (m, 1H), 2.24-2.36 (m, 1H), 2.41-2.60 (m, 2H), 2.94-3.14 (m, 2H), 3.19-3.34 (m, 2H), 4.68 (s, 2H), 6.60 (s, 1H), 7.28-7.34 (m, 1H), 7.40 (dd, 1H), 7.46-7.49 (m, 2H), 7.52 (ddd, 1H), 7.62 (s, 1H), 7.73 (dd, 1H).

Provenance & Evidence