[CH3:1][C:2](=[CH2:5])[CH2:3][OH:4].[O-:6]O.C1(C(C)C)C=CC=CC=1.P(OC)(OC)OC.C(N(CC)CC)C.[N+:31]([C:34]1[CH:35]=[C:36]([S:40](Cl)(=[O:42])=[O:41])[CH:37]=[CH:38][CH:39]=1)([O-:33])=[O:32]>CN(C)C1C=CN=CC=1.C(Cl)Cl.CC(C)[O-].CC(C)[O-].CC(C)[O-].CC(C)[O-].[Ti+4]>[CH3:5][C@@:2]1([CH2:1][O:41][S:40]([C:36]2[CH:37]=[CH:38][CH:39]=[C:34]([N+:31]([O-:33])=[O:32])[CH:35]=2)(=[O:42])=[O:6])[CH2:3][O:4]1To an oven-dried 1000 mL three-necked flask was added powdered activated molecular sieves (8.0 g, 4 Å) and CH2Cl2 (440 mL), D-(−)-diisopropyl tartrate (4 mL, 14.2 mmol) and 2-methyl-2-propene-1-ol (20 mL, 240 mmol) was added and the mixture was cooled to −20° C. Titanium tetraisopropoxide (3.5 mL, 11.9 mmol) was added with a few mL of CH2Cl2 and the mixture was stirred at −20° C. for 30 min. Cumene hydroperoxide (75 mL, 430 mmol) was added dropwise over 1.5 hours maintaining the temperature at −20° C. The mixture was stirred at this temperature overnight. Trimethyl phosphite (40 mL, 340 mmol) was added dropwise over 5 hours maintaining the temperature at −20° C. Triethylamine (50 mL, 360 mmol) and 4-dimethylaminopyridine (DMAP) (3.48 g, 28.5 mmol) was added followed by a solution of 3-nitrobenzenesulphonyl chloride (47 g, 212 mmol) in CH2Cl2 (400 mL). The temperature was raised to −10° C. and the mixture was stirred at this temperature overnight. After removing the external cooling vessel, the reaction mixture was filtered through celite. The organic phase was washed with 10% tartaric acid (500 mL), saturated NaHCO3 (300 mL) and brine (300 mL). The organic layer was dried over magnesium sulphate (MgSO4) and concentrated in vacuo to give 150 g of a yellow oil. The crude material was purified by silica gel flash chromatography (0-50% ethyl acetate in heptane) to give the subtitled compound (48.8 g).
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