Methanol → 1h-Indazole-1-carboxylic acid,5-amino-3-phenyl-,1,1-dimethylethyl ester

HRID 1452830Notes

Reaction equation

C([O-])=O.[NH4+].[C:5]([O:9][C:10]([N:12]1[C:20]2[C:15](=[CH:16][C:17]([N+:21]([O-])=O)=[CH:18][CH:19]=2)[C:14]([C:24]2[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=2)=[N:13]1)=[O:11])([CH3:8])([CH3:7])[CH3:6].CO>[Pd].O>[NH2:21][C:17]1[CH:16]=[C:15]2[C:20](=[CH:19][CH:18]=1)[N:12]([C:10]([O:9][C:5]([CH3:8])([CH3:7])[CH3:6])=[O:11])[N:13]=[C:14]2[C:24]1[CH:25]=[CH:26][CH:27]=[CH:28][CH:29]=1

Participants

Conditions

Temperature: 20 °C

Procedure

5-Amino-N-tert-butoxycarbonyl-3-phenyl-1H-indazole can be obtained in the following way: 0.12 g of 10% palladium-on-charcoal and 0.68 g of ammonium formate are added to a solution of 0.8 g of N-tert-butoxycarbonyl-5-nitro-3-phenyl-1H-indazole and of 14 ml of methanol. The suspension is maintained with stirring for 18 hours at a temperature in the region of 20° C. 50 ml of distilled water are added to the reaction medium which is extracted with 50 ml and 25 ml of ethyl acetate. The organic phases are pooled, dried over magnesium sulfate, filtered, and concentrated by evaporation under reduced pressure. The residue obtained is purified by chromatography on a silica column with dichloromethane as eluent. 0.6 g of 5-amino-N-tert-butoxycarbonyl-3-phenyl-1H-indazole is thus obtained in the form of an off-white solid melting at 191° C.

Workup

temperatureThe suspension is maintained
extractionis extracted with 50 ml and 25 ml of ethyl acetate
dry with materialdried over magnesium sulfate
filtrationfiltered
concentrationconcentrated by evaporation under reduced pressure
customThe residue obtained
customis purified by chromatography on a silica column with dichloromethane as eluent

Sources & evidence

ORD record: ord-1ce09f7d77ce42f68c019136c4d695df
Source dataset: uspto-grants-2009_01
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US07473701B2

Reaction notes

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