[CH3:1][NH:2][C:3]1[CH:8]=[N:7][CH:6]=[CH:5][N:4]=1.[CH3:9][O:10][C:11]1[CH:16]=[CH:15][C:14]([CH3:17])=[CH:13][C:12]=1[N:18]=[C:19]=[O:20].CCOC(C)=O.CCCCCC.C(Cl)Cl.CO>ClC(Cl)C>[CH3:9][O:10][C:11]1[CH:16]=[CH:15][C:14]([CH3:17])=[CH:13][C:12]=1[NH:18][C:19](=[O:20])[N:2]([CH3:1])[C:3]1[CH:8]=[N:7][CH:6]=[CH:5][N:4]=1To a 0.3 M stirred solution of 2-methylaminopyrazine (1 equiv.) in dichloroethane at room temperature under nitrogen was added 2-methoxy-5-methylphenylisocyanate (1 equiv.). The reaction was warmed to 80° C. overnight and then cooled to room temperature. In most cases, the product precipitated and was isolated by filtration. Alternatively the product could be isolated by silica gel chromatography using EtOAc/hexane or CH2Cl2/MeOH as eluant. 1H-NMR (400 MHz, CDCl3) δ8.57 (s, 1H), 8.32 (s, 1H), 8.31 (s, 1H), 8.17 (s, 1H), 6.80 (i, 2H), 3.90 (s, 3H), 3.56 (s, 3H), 2.32 (s, 3H). LRMS (ESI, Positive) m/e 273.2 (M+1).
読み込み中…
