Methanol → [5-(Butylsulfanyl)thiophen-2-yl]methanol
反応式
[BH4-].[Na+].C([C:7]1[S:11][C:10](C=S)=[CH:9][CH:8]=1)CCC.[CH3:14][OH:15]>[OH-].[Na+].C1COCC1>[OH:15][CH2:14][C:10]1[S:11][C:7]([S:11][CH2:10][CH2:9][CH2:8][CH3:7])=[CH:8][CH:9]=1[BH4-].[Na+].C([C:7]1[S:11][C:10](C=S)=[CH:9][CH:8]=1)CCC.[CH3:14][OH:15]>[OH-].[Na+].C1COCC1>[OH:15][CH2:14][C:10]1[S:11][C:7]([S:11][CH2:10][CH2:9][CH2:8][CH3:7])=[CH:8][CH:9]=1A solution of NaBH4 (5.3 g, 0.141 mol) in methanol (29.0 g) and sodium hydroxide (20%, 56.0 mL) was added dropwise to a solution of 45 (56.47 g, 0.282 mol) in THF (75 mL) at room temperature. The mixture was stirred for 2 hours, extracted with ethyl ether 3×150 mL), the combined extracts washed with brine and dried (MgSO4). After solvent removal, the crude product 46 was obtained as an oil (55.4 g, 97%); 1H NMR δ: 0.88 (t, 3 H, J=7.3 Hz, CH3), 1.39 (m, 2 H, CH3—CH2), 1.57 (m, 2 H, CH3—CH2—CH2),1.88 (s, 1 H OH), 2.76 (t, 2 H, J=7.3 Hz, CH2—S), 4.73 (s, 2 H, CH2—OH), 6.83 (d, 1 H, J=3.5 Hz, aromatic H), 6.94 (d, 1 H, J=3.5 Hz, aromatic H); λmax/nm (εmax/dm3 mol−1cm−1) 275.5 (3600); LRMS(EI+) calc. for C9H14OS2: 202.1, found 202.1. The product was used without further purification in the preparation of 47.
読み込み中…
