Ammonium Chloride → HCID 86718972, compound

Participants

Reaction Steps

To a stirred solution of allylic alcohol 11 (4 g, 12.7 mmol) was added dess marline (8.1 g, 19.7 mmol) at 0° C. The mixture was warm to ambient temperature and stirred for 1 hr. The mixture was passed through celite bed and obtained filtrate was concentrated under reduced pressure to give crude allylic ketone, which was proceeded as such in next step without further purification. The crude allylic ketone (3.5 g, 11.1 mmol) was dissolved in anhydrous methanol, cooled the solution at −78° C. Added CeCl3.7H2O (5.8 g, 15.6 mmol) at −78° C. and after 10 minutes stirring NaBH4 (0.54 g, 14.5 mmol) was added at one portion. After 15 min stirring at −78° C., the reaction mixture was allowed to 0° C. then saturated NH4Cl (30 mL) was added and the mixture was allowed to stir for 1 hr. Solvent was removed under reduced temperature and pressure and the residue was extracted with DCM (200 mL×2). The combined DCM extracts were washed with brine (40 mL×2), dried over anhydrous Na2SO4, filtered and concentrated under vacuum. The residue was purified by flash silica gel column chromatography (5% EtOAc/hexane) to give compound 12 (3.2 g, 80%) as oil. [α]22D −96.878° (c 2.01, CHCl3); 1H NMR (500 MHz, CDCl3) δ 5.26(s, 1H), 5.10 (s, 1H), 4.52 (m, 2, 3- H's, 2H), 4.4 (m, 1H, 1-H′), 3.71 (dd, J=4 & 10 Hz, 1H, 5- Ha), 3.53 (dd, J=4 & 10 Hz, 5- Hb, 1H), 2.57 (br, 1H), 2.29 (d, J=10.5 Hz, D2O exchange, OH), 1.38 (s, 3H), 1.30 (s, 3H), 0.85 (m, 9H), 0.013-0.006 (m, 6H). 13C NMR(125 MHz, CDCl3) 159.01, 115.9, 115.4, 86.85, 84.85, 79.48, 71.63, 57.21, 32.13, 31.54, 30.33, 23.83, 0.015; HR-MS Calcd. For (C16H30O4Si+H)+ 315.1913, found 315.1987.

Provenance & Evidence