[CH3:1][O:2][C:3]([C:5]1[N:6]=[C:7]([CH3:19])[S:8][C:9]=1[C:10]1[CH:15]=[CH:14][CH:13]=[C:12]([N+:16]([O-])=O)[CH:11]=1)=[O:4].[Cl-].[NH4+]>CCO.O.C(Cl)Cl.[Fe]>[CH3:1][O:2][C:3]([C:5]1[N:6]=[C:7]([CH3:19])[S:8][C:9]=1[C:10]1[CH:15]=[CH:14][CH:13]=[C:12]([NH2:16])[CH:11]=1)=[O:4]Iron powder (53.7 mmol) is added to a suspension of 2-methyl-5-(3-nitro-phenyl)-thiazole-4-carboxylic acid methyl ester (44.1 mmol) and ammonium chloride (221 mmol) in a mixture of EtOH (100 mL) and water (50 mL). The mixture is stirred at 80° C. for 4 h, iron powder (53.7 mmol) is added and heating is continued for additional 3 h. After addition of a third portion of iron powder (26.8 mmol) the mixture is heated at 80° C. for additional 3 h, cooled to RT, diluted with DCM and filtered through Celite. The residue is washed with DCM and water and the filtrate is concentrated in vacuo. A sat. aqueous NaHCO3 solution and DCM are added and the layers are separated. The organic layer is washed with water, dried over MgSO4 and concentrated in vacuo to give a crude product which is used without further purification. LC-MS: tR=0.67 min; [M+H]+=249.4.
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