Sodium Hydroxide → 6-amino-5-ethynyl-1H-indazole-7-carboxylic acid

HRID 245625Notes

Reaction equation

C[O:2][C:3]([C:5]1[C:6]([NH2:16])=[C:7]([C:14]#[CH:15])[CH:8]=[C:9]2[C:13]=1[NH:12][N:11]=[CH:10]2)=[O:4].[OH-].[Na+]>O1CCOCC1.CO>[NH2:16][C:6]1[C:5]([C:3]([OH:4])=[O:2])=[C:13]2[C:9]([CH:10]=[N:11][NH:12]2)=[CH:8][C:7]=1[C:14]#[CH:15]

Participants

Conditions

Temperature: 50 °C

Procedure

To a solution of 200 mg (0.93 mmol) of 6-amino-5-ethynyl-1H-indazole-7-carboxylic acid methyl ester in 4.2 mL of dioxane and 0.2 mL of methanol is added 2.3 mL (2.3 mmol) of a 1N aqueous solution of NaOH. The mixture is stirred for 5 hours at 50° C. The solvents are evaporated and water is added to the residue. The product is precipitated at pH 4 by addition of 1N aqueous HCl, filtrated, washed with a minimum of water and dried by azeotropic distillation with toluene. The yellowish solid obtained is used directly in the next step; LC/MS: 202/203 (M+H)+.

Workup

customThe solvents are evaporated
additionwater is added to the residue
customThe product is precipitated at pH 4 by addition of 1N aqueous HCl
filtrationfiltrated
washwashed with a minimum of water
dry with materialdried by azeotropic distillation with toluene
customThe yellowish solid obtained

Sources & evidence

ORD record: ord-4a0bd77d286b46f1ab33f71fb644bc13
Source dataset: uspto-grants-2014_02
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08658801B2

Reaction notes

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