Dimethylformamide → 6-amino-5-cyano-1H-indazole-7-carboxylic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

To a solution of 500 mg (1.85 mmol) of 6-amino-5-bromo-1H-indazole-7-carboxylic acid methyl ester, prepared as in step a in example 16, in 10 mL of N,N-dimethylformamide under an atmosphere of argon is added 135 mg (1.15 mmol) of zinc cyanide and 206 mg (0.185 mmol) of tetrakis(triphenylphsophine)palladium. The reaction mixture is stirred in a microwave oven at 180° C. for 5 minutes. Then, a 1:1 v/v mixture of ethyl acetate and tertbutylmethyl ether and brine are added to the reaction and the phases are separated. The aqueous layer is extracted with tert-butylmethylether. The organic extracts are washed twice with brine, dried over MgSO4 and concentrated in vacuo. The residue is purified by flash chromatography (SiO2, hexane/ethyl acetate 2:1 to 1:1, gradient) to afford 380 mg of product (94%) as a yellowish solid; LC/MS:217/218 (M+H)+.

Provenance & Evidence