2,4,6-Trimethylpyridine → (2S,3S)-3-(Triethylsilyloxy)-2-methylhexanal

반응식

[CH3:1][C@@:2]1([CH2:8][OH:9])[C@H:4]([CH2:5][CH2:6][CH3:7])[O:3]1.[Si:10](OS(C(F)(F)F)(=O)=O)([CH2:15][CH3:16])([CH2:13][CH3:14])[CH2:11][CH3:12].N1C(C)=CC(C)=CC=1C.[Si](O[C@H](CCC)[C@@H](C)C=O)(C(C)(C)C)(C)C>>[CH2:11]([Si:10]([CH2:15][CH3:16])([CH2:13][CH3:14])[O:3][C@@H:4]([CH2:5][CH2:6][CH3:7])[C@H:2]([CH3:1])[CH:8]=[O:9])[CH3:12]

참가 물질

반응물 4

HCID 79532,4,6-Trimethylpyridine

HCID 2733308Triethylsilyl trifluoromethanesulphonate

HCID 10931464(2R,3S)-2-Methyl-3-propyloxiranemethanol

HCID 14959487(2R,3R)-3-[t-Butyldimethylsilyloxy)-2-methylhexanal

생성물 1

HCID 57173492(2S,3S)-3-(Triethylsilyloxy)-2-methylhexanal

실험 절차

Epoxy alcohol 13, 1.4 eq TESOTf, and 1.5 eq of collidine were reacted as in the preparation of 16 to give 95%+yield (<20:1 de) of crude aldehyde 22 which was chromatographed (SiO2, 3% EtOAc/96% Hex/1% TEA) to give 85% of 22. 1H NMR (CDCl3, 500.135 MHz) δ:9.68 (1H, d, J=2.37 Hz), 3.89 (1H, q, J=5.03 Hz), 2.43 (1H, qdd, J=6.95, 5.03, 2.30 Hz), 1.5-1.2 (4H, m), 1.02 (3H, d, J=6.95 Hz), 0.89 (6H, t J=8.0 Hz), 0.85 (3H, t, J=7.14 Hz), and 0.54 (9H, q, J=7.80 Hz). 13C NMR (CDCl3, 90.55 MHz) δ:205.1, 73.3, 51.3, 37.2, 18.1, 14.1, 10.3, 6.4, and 5.1. IR (thin film): 2957 (s), 2938 (s), 2912 (s), 2877 (s), 1726 (s), 1459 (s), 1415 (w), 1379 (w), 1239 (m), 1155 (w), 1074 (s), 1038 (m), 1005 (w), and 741 (s) cm-1. high resolution MS (m/z): 215. 1467, calcd for C11H23O2Si 215.1467 (M-C2H5). [α]D =+14.7° (c=1.89, CH2Cl2). 1H NMR integration of δ 9.69 to δ 9.72 indicated a 90.3:9.7 ratio.