Methyl 3-amino-4-methylbenzoate → methyl 1H-indazole-6-carboxylate

Reaction equation

[NH2:1][C:2]1[CH:3]=[C:4]([CH:9]=[CH:10][C:11]=1[CH3:12])[C:5]([O:7][CH3:8])=[O:6].[N:13]([O-])=O.[Na+]>CC(O)=O.O>[NH:1]1[C:2]2[C:11](=[CH:10][CH:9]=[C:4]([C:5]([O:7][CH3:8])=[O:6])[CH:3]=2)[CH:12]=[N:13]1

Participants

Procedure

To a solution of methyl 3-amino-4-methylbenzoate D-1 (5.0 g, 30 mmol) in AcOH (140 mL) at 0° C. was added a solution of sodium nitrite (2.1 g, 30 mmol) in H2O (3.5 mL). After addition, the mixture was stirred at rt for 24 h. Then half of the solvent was removed under reduced pressure and the resulting mixture was diluted with H2O, and extracted with EtOAc. The combined organics were washed H2O and brine, and concentrated to give the title compound. LCMS (ESI) calc'd for C9H9N2O2 [M+H]+: 177. found 177.