CCN(CC)CC.[CH3:8][S:9](Cl)(=[O:11])=[O:10].[CH2:13]([OH:33])[CH2:14][CH2:15][CH2:16]/[CH:17]=[CH:18]\[CH2:19]/[CH:20]=[CH:21]\[CH2:22]/[CH:23]=[CH:24]\[CH2:25]/[CH:26]=[CH:27]\[CH2:28]/[CH:29]=[CH:30]\[CH2:31][CH3:32]>C(Cl)Cl>[CH3:8][S:9]([O:33][CH2:13][CH2:14][CH2:15][CH2:16]/[CH:17]=[CH:18]\[CH2:19]/[CH:20]=[CH:21]\[CH2:22]/[CH:23]=[CH:24]\[CH2:25]/[CH:26]=[CH:27]\[CH2:28]/[CH:29]=[CH:30]\[CH2:31][CH3:32])(=[O:11])=[O:10]Et3N (1.50 mL, 10.8 mmol) and methanesulfonyl chloride (402 μL, 5.20 mmol) was added to a solution of (5Z,8Z,11Z,14Z,17Z)-icosa-5,8,11,14,17-pentaen-1-ol (1.15 g, 4.0 mmol) in CH2Cl2 (40 mL) held at 0° C. under nitrogen. The mixture was stirred at 0° C. for one hour, and poured into ice-water (100 g) and the water phase extracted with Et2O (50 mL). The combined organic extracts were added 0.5 M H2SO4 (35 mL), the organic phase washed with NaHCO3 (sat. aq.) (25 mL), before dried (Mg2SO4, gram). Filtration and concentration in vacuo afforded 1.24 gram of crude oil. Purification on Armen, SVP D26 column packed with 30 gram of 15-40 μm Merck silica, flow 20 mL/min, UV 210 nm and collecting 15 mL fraction, was performed using gradient elution: (starting heptane:EtOAc (100:0) and increasing during 10 min. to 10% EtOAc, then increasing 5 min. to 20% EtOAc (hold 10 min.), then increasing in 5 min. to 40% EtOAc (hold 0 min.). Fractions 6-14 afforded 1.16 g (79% yield) of the title compound as oil.
読み込み中…
