Dimethyl Sulfide → (3RS,4S)-2-methyl-4-(trityl-amino)-hexan-3-ol

참여 물질

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To a stirred suspension of CuBr.SMe2 (1.37 g, 2.2 eq, 6.66 mmol) in ether (100 mL) under an argon atmosphere at −78° C., was added isopropyllithium (0.7 M in pentane, 17.29 mL, 4 eq, 12.1 mmol) dropwise and the solution allowed to warm to room temperature. The mixture was recooled to −70° C., to which was added a solution of (S)-2-(trityl-amino)-butyraldehyde (1 g, 1 eq, 3.03 mmol) in ether (25 mL) dropwise with stirring. The reaction mixture was stirred at this temperature for 1 h, then allowed to warm to −55° C. and stirred at this temperature for 3 h. To the reaction mixture was added a saturated aqueous solution of NH4Cl (100 mL) and allowed to warm to room temperature over 16 h The reaction mixture was extracted with ether (2×200 mL), and the combined organic phase washed with brine (50 mL), dried (MgSO4) and evaporated in vacuo. The residue was purified by silica gel column chromatography, eluted with hexane:ether (100:0→90:10) to afford the title compound as a colourless oil; Yield: 0.36 g (32%). (50% de 3R,4S, 50% de 3S,4S). 1H-NMR (d6-DMSO, 250 MHz): δ 0.44 (t, 3H, J=6.79 Hz, —NHCH(CH2CH3)CH(CH(CH3)2)OH), 0.52+0.76 (2×d, 6H, J=6.63 Hz, —NHCH(CH2CH3)CH(CH(CH3)2)OH), 0.80-1.15 (m, 2H, —NHCH(CH2CH3)CH(CH(CH3)2)OH), 1.70 (m, 1H, —NHCH(CH2CH3)CH(CH(CH3)2)OH), 2.10 (m, 1H, —NHCH(CH2CH3)CH(CH(CH3)2)OH), 2.76 (m, 1H, —NHCH(CH2CH3)CH(CH(CH3)2)OH), 2.99 (m, 1H, —NHCH(CH2CH3)CH(CH(CH3)2)OH), 4.55 (d, 1H, J=5.84 Hz, —NHCH(CH2CH3)CH(CH(CH3)2)OH), 7.17-7.46 (m, 15H, 3×Bz).

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