反应详情

To a solution of 15a (245 mg, 0.54 mmol) in CH3CN (3 mL), HCl (1M aqueous solution, 350 μL, 0.35 mmol), phenylboronic acid (62 mg, 0.51 mmol) and n-hexane (3 mL) were sequentially added and the resulting biphasic solution was vigorously stirred. After 30 min the n-hexane layer, containing the pinanediol phenylboronate, was removed and fresh n-hexane (3 mL) was added. This last procedure was repeated several times until a TLC analysis revealed no remaining pinanediol boronate. The acetonitrile phase was then concentrated affording 16 as a yellowish solid (159 mg, 92% yield). Mp 107° C. (dec). [α]D+78.0 (c 1.0, MeOH). 1H-NMR (400 MHz, MeOD): δ 2.83 (2H, d, J 7.1, CHCH2), 3.05 (1H, t, J 7.1, BCH), 4.20 (2H, s, CH2SO2), 7.16-7.44 (10H, m, HArom). 13C-NMR (100 MHz, MeOD): δ 38.8, 39.3 (CB), 58.6, 126.1, 127.2, 128.0, 128.2, 129.0, 130.1, 130.6, 133.3. EI-MS and elemental analysis were not obtainable, but exposure of 16 to an equimolar amount of (+)-pinanediol in anhydrous THF afforded compound 15a in quantitative yield and satisfactory elemental analysis; Anal. Calcd. for C25H32BNO4S: C, 66.23; H, 7.11; N, 3.09; S, 7.07. Found: C, 66.14; H, 6.91; N, 3.32; S, 6.89.

1. customwas removed
2. additionfresh n-hexane (3 mL) was added
3. concentrationThe acetonitrile phase was then concentrated