反应 #3342768
相关文献 (1)
openreactiondata ↗doi:10.6084/m9.figshare.5104873.v1; patent:US06953781B2
反应条件: temp:70.01; pressure:0.00; stir:; See reaction.notes.procedure_details.
实验步骤: 3-O-methyl-D-chiro-inositol (D-pinitol) (283 mg, 1.457 mmol, 1 equiv) was dissolved in methanol (15 mL), then 1,2-cyclohexane diacetal (507 mg, 2.458 mmol, 1.7 equiv), trimethyl orthoformiate (200 mL, 1.752 mmol, 1.2 equiv) and 1-(S)-(+)-10-camphorsulfonic acid (24 mg, 0.102 mmol, 0.07 equiv) were added. The reaction mixture was heated at 70° C. for 24 h whereupon it was diluted with MeOH and quenched with solid NaHCO3. The residue was concentrated and purified by flash chromatography (Hex/EtOAc 1:15) to give 6 (222 mg, 0.664 mmol, 45%; 89% based on 134 mg of recovered D-pinitol). Rf(Hex/EtOAc 1:20):0.22; [α]20D −22.9 (c=1.05, CHCl3); 1H NMR (CDCl3, 300 MHz): d=4.12 (Ys, 1H, H1), 4.10 (s, 2H, H4, H5), 4.07 (Ys, 1H, H6), 3.81 (dt, 1H, J2-3=9.0 Hz, J2-1=3.6 Hz, J2-OH=1.8 Hz, H2), 3.47 (t, 1H, J=9.0 Hz, H3), 3.23 (s, 3H, OCH3), 3.21 (s, 3H, OCH3), 2.76 (d, 1H,JOH-2=1.8 Hz, OH2), 2.60 (s, 1H, OH1), 2.56 (s, 1H, OH−6), 1.86-1.78 (m, 1H, CDA), 1.77-1.66 (m, 3H, CDA), 1.57-1.50 (m, 2H, CDA), 1.42-1.34 (m, 2H, CDA); 13C-NMR (CDCl3, 75 MHz); d=98.9 (C), 98.0 (C), 80.2 (C3), 71.5(C2), 70.8, 70.4, 70.3 (C1, C4, C6), 68.7 (C5), 61.1 (OCH3), 47.0(OCH3, CDA), 46.8 (OCH3, CDA), 27.1 (CH2), 27.0 (CH2), 21.5 (CH2), 21.4 (CH2); HRFABMS Calcd. for C15H26O8: 357.3571 found: 357.1528; MALDI-TOF Calcd. for C15H2O8+Na+: 357.4. found: 357.5. calcd. for C15H26O8+K+: 373.5. found: 374.1 quenched with solid NaHCO3 The residue was concentrated purified by flash chromatography (Hex/EtOAc 1:15)
来源 ID: ord-7bd942f955b2442ea622e690421c9956