[CH3:1][C:2]1([CH3:9])[CH2:7][CH2:6][CH2:5][CH:4]([OH:8])[CH2:3]1.C(N(CC)CC)C.[C:17]1([CH3:27])[CH:22]=[CH:21][C:20]([S:23](Cl)(=[O:25])=[O:24])=[CH:19][CH:18]=1>CN(C1C=CN=CC=1)C.C(Cl)Cl>[CH3:27][C:17]1[CH:22]=[CH:21][C:20]([S:23]([O:8][CH:4]2[CH2:5][CH2:6][CH2:7][C:2]([CH3:9])([CH3:1])[CH2:3]2)(=[O:25])=[O:24])=[CH:19][CH:18]=1Under a nitrogen atmosphere, add 3,3-dimethylcyclohexanol (1 g, 9.75 mmol), DMAP (238 mg, 1.95 mmol), triethylamine (2.70 mL, 19.5 mmol), and p-toluenesulfonyl chloride (2.045 g, 10.72 mmol) to DCM (25 mL) at 0° C. Stir the mixture for 1 h at 0° C. and warm to room temperature overnight. Add saturated aqueous NaHCO3 (20 mL) and separate the layers. Extract the aqueous layer with DCM (3×20 mL). Wash the combined organic extracts with water and brine. Dry the organic phase over Na2SO4, filter, and concentrate in vacuo. Purify the crude mixture by chromatography on silica gel (45 g, pre-packed cartridge) eluting with hexane/EtOAc (1:0 to 1:1 gradient over 60 min, 80 mL/min) to obtain the desired intermediate as a clear oil (1.93 g, 70%). MS (APCI+) m/z: 283 (M+H)+.
Loading…
