2-Aminophenylboronic acid hydrochloride → 4-(2-aminophenyl)-1-butyl-5-methyl-1H-pyrazole-3-carbonitrile

Participants

Reaction Steps

A modification of the method described in Part G of Examples 1-4 was used to couple 4-bromo-1-butyl-5-methyl-1H-pyrazole-3-carbonitrile (2.42 g, 10.0 mmol) and 2-aminophenylboronic acid hydrochloride (2.43 g, 14.0 mmol). Palladium (II) acetate was added as a 5 mg/mL solution in toluene (1.3 mL). The reaction was heated under nitrogen for 17 hours and combined with the product mixture from another run before being subjected to the work-up procedure. The crude product was purified by chromatography on a HORIZON HPFC system (40+M cartridge, eluting with chloroform:CMA in a gradient from 100:0 to 80:20) to provide 3.17 g of 4-(2-aminophenyl)-1-butyl-5-methyl-1H-pyrazole-3-carbonitrile as an orange oil. A small amount (0.21 g) of 2-butyl-1-methyl-2H-pyrazolo[3,4-c]quinolin-4-amine was also obtained as a beige powder.

Provenance & Evidence