[C:1]([O:8][CH3:9])(=[O:7])/[CH:2]=[CH:3]/[C:4]([OH:6])=[O:5].C(=O)([O-])O.[Cs+].Cl[CH2:16][CH2:17][O:18][C:19]([O:21][CH:22]([CH3:24])[CH3:23])=[O:20]>CN1C(=O)CCC1>[C:1]([O:8][CH3:9])(=[O:7])/[CH:2]=[CH:3]/[C:4]([O:6][CH2:16][CH2:17][O:18][C:19]([O:21][CH:22]([CH3:24])[CH3:23])=[O:20])=[O:5]Following general procedure A, methyl hydrogen fumarate (0.39 g, 3.0 mmol) in NMP (8 mL) was reacted with CsHCO3 (0.69 g, 3.6 mmol) and methylethyl (chloroethoxy)formate (0.70 g, 4.2 mmol) to afford 0.71 g (91% yield) of the title compound (40) after isolation and purification. 1H NMR (CDCl3, 400 MHz): δ 6.89 (d, J=15.6 Hz, 1H), 6.84 (q, J=5.2 Hz, 1H, superimposed), 6.82 (d, J=15.6 Hz, 1H, superimposed), 4.90 (heptet, J=6.2 Hz, 3H), 3.81 (s, 3H), 1.57 (d, J=5.2 Hz, 3H), 1.32 (d, J=6.2 Hz, 3H), 1.31 (d, J=6.2 Hz, 3H). MS (ESI): m/z 261.02 (M+H)+.
Wird geladen…
