C1N=C[N:3](C(N2C=NC=C2)=O)[CH:2]=1.[NH2:13][C:14]1[CH:22]=[C:21]([Cl:23])[CH:20]=[CH:19][C:15]=1[C:16](O)=[O:17].CN>C1COCC1>[NH2:13][C:14]1[CH:22]=[C:21]([Cl:23])[CH:20]=[CH:19][C:15]=1[C:16]([NH:3][CH3:2])=[O:17]Carbonyl-1,1′-diimidazole (1.70 g) was added to 2-amino-4-chlorobenzoic acid (1.50 g) in THF (22.2 mL). After stirring overnight a solution of methylamine in THF (2M, 6.6 mL) was added and the reaction stirred for 3 hours. The reaction was concentrated in vacuo and the residue dissolved in EtOAc (100 mL) and saturated aqueous sodium bicarbonate solution (50 mL). The organics were then washed with saturated aqueous sodium bicarbonate solution (50 mL) and then water (2×100 mL). The organics were extracted with 1 M HCl (4×25 mL, then 2×100 mL then 50 mL), the aqueous phase basified with potassium carbonate (˜50 g) and the organics discarded. The aqueous was then extracted with EtOAc (2×50 mL). The combined organics were dried (MgSO4, 10 g) and concentrated to give 2-amino-4-chloro-N-methylbenzamide (1.2 g, 74%).
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