methyl 1-(4-nitrobenzyl)-1H-1,2,4-triazole-5-carboxylate → methyl 1-(4-aminobenzyl)-1H-1,2,4-triazole-5-carboxylate
Reaction equation
[N+:1]([C:4]1[CH:19]=[CH:18][C:7]([CH2:8][N:9]2[C:13]([C:14]([O:16][CH3:17])=[O:15])=[N:12][CH:11]=[N:10]2)=[CH:6][CH:5]=1)([O-])=O>[C].[Pd].C(O)C>[NH2:1][C:4]1[CH:5]=[CH:6][C:7]([CH2:8][N:9]2[C:13]([C:14]([O:16][CH3:17])=[O:15])=[N:12][CH:11]=[N:10]2)=[CH:18][CH:19]=1Participants
4
Procedure
A mixture of methyl 1-(4-nitrobenzyl)-1H-1,2,4-triazole-5-carboxylate (1.3 g), 10% palladium carbon (130 mg) and ethanol (200 ml) was stirred under a hydrogen atmosphere at room temperature for 2 hrs. Palladium carbon was removed from the reaction mixture by filtration, and the filtrate was concentrated. The residue was subjected to silica gel column chromatography to give methyl 1-(4-aminobenzyl)-1H-1,2,4-triazole-5-carboxylate (0.88 g, 76%) as crystals from a fraction eluted with hexane-ethyl acetate (1:2, v/v). Recrystallization thereof from ethyl acetate-isopropyl ether gave colorless prism crystals. melting point: 101-103° C.