反应详情

This synthesis is depicted in FIG. 11. L-Selectride (d, lithium tri(sec-butyl)hydridoborate, 4 ml of a 1M solution in THF, 4 mmol) was added dropwise at 0° to a solution of ketone 10 (800 mg, 3.10 mmol) in dry ether (5 ml). After stirring for 1 h at 0°, water was added (10 ml). The boranes were oxidized by adding 10% aq. NaOH-solution (5 ml), followed by 30% aq. H2O2 -solution (3 ml) and stirring for 3 h at RT. After workup (ether), the crude product (790 mg, Ca. 9:1 mixture of 11 and 12) was chromatographed on silica gel with CH2Cl2 to give 700 mg (87%) of pure alcohol 11. M.p. 119°-120°→123°-124° (from PE), [a]D +40.6° (C=1.0).--IR. (CHCl3): 3640m, 3500 br., 1585w.--1H-NMR. (90 MHz): 0.78 (s, 3H); 4.09 (m, w1/2 ≈8, 1H); 5.71 (m, 1H), 5.87 (m, 1H).

1. stirringstirring for 3 h at RT
2. customAfter workup (ether), the crude product (790 mg, Ca. 9:1 mixture of 11 and 12) was chromatographed on silica gel with CH2Cl2