[C:1]1([CH3:10])[CH:6]=[CH:5][C:4]([S@@:7]([NH2:9])=[O:8])=[CH:3][CH:2]=1.[CH3:11][C@H:12]([C@H:15]([CH3:19])[CH2:16][CH2:17][CH3:18])[CH:13]=O>C1COCC1.[Cl-].[Na+].O.[O-]CC.[Ti+4].[O-]CC.[O-]CC.[O-]CC>[CH3:11][C@H:12]([C@H:15]([CH3:19])[CH2:16][CH2:17][CH3:18])[CH:13]=[N:9][S:7]([C:4]1[CH:5]=[CH:6][C:1]([CH3:10])=[CH:2][CH:3]=1)=[O:8]Titanium(IV) ethoxide (5.16 g, 22.6 mmol) and (S)-(+)-p-toluenesulfinamide (7.02 g, 45.2 mmol) were added to (2R,3R)-2,3-dimethyl-hexanal (2.9 g, 22.6 mmol) in dry THF (30 mL). The resulting mixture was stirred at room temperature for 18 hours and poured into a brine solution (40 mL). The slurry was rapidly stirred for 10 minutes and filtered. The filtrate was extracted into ethyl acetate, washed with brine and dried over MgSO4. The solvent was evaporated and the residue was filtered through a silica plug, eluting with 50/50 solution of hexane/ethyl acetate to afford the titled compound (3.1 g, 51.6% yield) as an oil: 1H NMR (400 MHz, CDCl3) δ ppm 0.8 (m, 6H) 1.1 (m, 4H) 1.3 (m, 3H) 1.7 (m, 1H) 2.4 (s, 3H) 2.5 (m, 1H) 7.3 (d, J=8.3 Hz, 2H) 7.5 (d, J=8.1 Hz, 2H) 8.1 (d, J=5.4 Hz, 1H). MS, m/z (relative intensity): 266 [M+1H, 100%].
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