反应详情

4-carboxyphthalic anhydride (1.0 g, 0.0052 mol) and 4-aminobutyric acid (0.54 g, 0.0052 mol) were refluxed as above for 7 hours. Crystallisation of the product from EtOH yielded 1.1 g (76%) of 102 as a white solid: mp=218-220° C.; Rf0.78 (A): Rf0.84 (C): Rf0.28 (D): 1H NMR (DMSO-d6); IR (cm−1): 2800-3250 (OH), 3050 (C═CH), 2680 (C—H), 1760 (C═O), 1712 (bs, C═O), 1560 (C═C), 1430 (C═C), 1397 (C—O), 1305 (C—O), 727 (C═CH); MS m/z (rel intensity) 277 (18), 276 (100).

1. customCrystallisation of the product from EtOH