Hippuric Acid → Oxazolone

反応式

[C:1]([NH:9][CH2:10][C:11]([OH:13])=[O:12])(=O)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[CH2:14]([O:16][CH:17](OCC)OCC)[CH3:15].C(OC(=O)C)(=O)C>CN(C1C=CN=CC=1)C>[CH2:14]([O:16]/[CH:17]=[C:10]1\[N:9]=[C:1]([C:2]2[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=2)[O:13][C:11]\1=[O:12])[CH3:15]

参加物

反応条件

温度: 140 °C

実験手順

To a mixture of 2-benzamidoacetic acid (2.5 g, 13.8 mmol), DMAP (0.017 g, 0.138 mmol) and triethoxymethane (2.3 ml, 13.8 mmol), was added acetic anhydride (2.6 ml, 27.6 mmol). The mixture was heated to 140° C. for 30 min. The solvent was removed in vacuo and purification by silica gel chromatography (0-30% ethyl acetate in hexanes) gave 1.4 g (47%) of (Z)-4-(ethoxymethylene)-2-phenyloxazol-5(4H)-one as an orange solid. 1H NMR (400 MHz, CDCl3) 8.09-8.04 (m, 2H), 7.56-7.51 (m, 1H), 7.50-7.43 (m, 2H), 7.35 (s, 1H), 4.43 (q, 2H), 1.49 (t, 3H).