[I:1][C:2]1[CH:3]=[C:4]([CH:9]=[CH:10][C:11]=1[CH3:12])[C:5]([NH:7][NH2:8])=[O:6].[C:13](OCC)(OCC)(OCC)[CH3:14]>C(O)(=O)C>[I:1][C:2]1[CH:3]=[C:4]([C:5]2[O:6][C:13]([CH3:14])=[N:8][N:7]=2)[CH:9]=[CH:10][C:11]=1[CH3:12]A stirred mixture of 3-iodo-4-methylbenzohydrazide (preparation 55b, 5.00 g, 18.1 mmol) and triethyl orthoacetate (11.00 mL, 58.2 mmol) in acetic acid (30 mL) were heated to 150° C. in a sealed tube. After 3 hours, the mixture was cooled and concentrated in vacuo. Aqueous sodium hydrogen carbonate solution was added and the mixture was extracted with dichloromethane. The organic solution was dried (MgSO4) and the solvent was removed in vacuo. The crude material was purified by flash chromatography (2:1 hexanes/ethyl acetate) to give the title compound (4.26 g, 78%) as a white solid.
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