Borane;tetrahydrofuran → HCID 12171880, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of ketone 13 (0.2 g, 1.16 mmol) in THF (2 ml) was added (R)-2-methyl-CBS-oxazaborolidine (0.35 ml of 1.0 M solution in toluene, 0.35 nmol, 0.3 equiv) at room temperature. To this solution was added borane-THF (0.755 ml of 1.0 M solution in THF, 0.755 mmol 0.65 equiv) dropwise. The reaction mixture was stirred at room temperature for 30 min after which time another portion of borane-THF (0.8 ml) was added and the mixture was stirred for an additional 3 hours. It was then cooled to 0° C. and quenched carefully by slow addition of water (2 ml). The mixture was extracted with ethyl acetate (3×4 ml). The organic extracts were dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to give a yellow color oil that was purified by flash column chromatography (EtOAc-hexanes, 1:7) to give the alcohol 9 (0.174 g, 86%) as a light yellow solid: [α]22D=−16.2 (c=0.9, CHCl3); TLC Rf=0.47 (silica gel, 25% hexanes/EtOAc); 1H NMR (600 MHz, CDCl3) δ 8.6-8.59 (d, 3J=4.8 Hz, 1H), 7.66-7.62 (m, 1H), 7.28-7.26 (d, 3J=7.8 Hz, 1H), 7.13-7.10 (m, 1H), 4.75-4.74 (m, 1H), 2.89-2.83 (m, 1H), 2.73-2.67 (m, 1H), 2.42-2.36 (m, 1H), 2.05 (s, 3H), 2.01-1.99 (d, 3J=7.8 Hz, 1H), 1.77-1.71 (m, 1H); 13C NMR (100 MHz, CDCl3) δ 156.750, 149.405, 140.980, 137.494, 136.153, 122.930, 121.717, 82.459, 32.923, 32.771, 13.301; HRMS calcd for C11H13NO+H+ 176.1075; found 176.1080 [M+H+].

Provenance & Evidence