[Br:1][C:2]1[CH:8]=[CH:7][C:5]([NH2:6])=[CH:4][C:3]=1[CH3:9].[C:10]1(=O)[O:15][C:13](=[O:14])[CH:12]=[CH:11]1>C(O)(=O)C>[Br:1][C:2]1[CH:8]=[CH:7][C:5]([N:6]2[C:13](=[O:14])[CH:12]=[CH:11][C:10]2=[O:15])=[CH:4][C:3]=1[CH3:9]4-Bromo-3-methylaniline (1.55 g, 8.33 mmol) and maleic anhydride (0.898 g, 9.16 mmol) were dissolved in acetic acid (10 mL) and heated at 115° C. for 12 h. The reaction was then cooled to 25° C. and the acetic acid was removed in vacuo. The resulting residue was suspended in 5% K2CO3 (100 mL), stirred for 25 minutes followed by filtering and rinsing with water. The material was then dried in vacuo to give compound 13B as a light brown solid (1.65 g). HPLC: 100% at 2.96 min (retention time) (YMC S5 ODS column 4.6×50 mm eluting with 10-90% aqueous methanol over 4 minutes containing 0.1% TFA, 4 mL/min, monitoring at 220 nm).
Wird geladen…