Diethyl (ethoxymethylene)malonate → (S)-Diethyl (7,8-Difluoro-3-Methyl-3,4-Dihydro-2H-[1,4]Benzoxazin-4-Yl)Methylene-Malonate
반응식
[F:1][C:2]1[CH:12]=[CH:11][C:5]2[NH:6][C@@H:7]([CH3:10])[CH2:8][O:9][C:4]=2[C:3]=1[F:13].C(O[CH:17]=[C:18]([C:24]([O:26][CH2:27][CH3:28])=[O:25])[C:19]([O:21][CH2:22][CH3:23])=[O:20])C>C1(C)C=CC=CC=1>[F:1][C:2]1[CH:12]=[CH:11][C:5]2[N:6]([CH:17]=[C:18]([C:19]([O:21][CH2:22][CH3:23])=[O:20])[C:24]([O:26][CH2:27][CH3:28])=[O:25])[C@@H:7]([CH3:10])[CH2:8][O:9][C:4]=2[C:3]=1[F:13]참가 물질
4
실험 절차
1.20 g (99.8% ee) of (3S)-7,8-difluoro-3-methyl-3,4-dihydro-2H-[1,4]benzoxazine was dissolved in toluene (0.5 ml). After adding diethyl ethoxymethylenemalonate (1.92 g), the mixture was stirred at 120 for 30 minutes and then at 140° C. under reduced pressure for 30 minutes. The residue was subjected to silica gel column chromatography. Thus, 2.19 g (99.8% ee) of the title compound was obtained as a yellow oily product. The physical constants of the obtained compounds was identical with those described in Japanese Patent No. 2,769,174.