1,2-Dimethoxyethane → 4-{4-[6-(3-Amino-phenyl)-imidazo[1,2-a]pyrazin-8-ylamino]-phenyl}-piperazine-1-carboxylic Acid Tert-Butyl Ester

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-(6-bromoimidazo[1,2-a]pyrazin-8-ylamino)benzoic acid ethyl ester (13) (4,33 mmol), 3-aminophenylboronic acid hemisulfate (5,63 mmol), tetrakis(triphenylphosphine)palladium (0.2 mmol), 1N aqueous sodium carbonate solution (13 mL), and dimethoxyethane (70 mL) is heated at 95° C. for 2 days. The mixture is allowed to cool, treated with water (100 mL), and extracted with ethyl acetate (3×80 mL). The extracts are washed with water (2×75 mL) and brine (1×75 mL), dried over magnesium sulfate, and evaporated in vacuo. The residue is chromatographed over silica gel, eluting with ethyl acetate, to give 4-{4-[6-(3-amino-phenyl)-imidazo[1,2-a]pyrazin-8-ylamino]-phenyl}-piperazine-1-carboxylic acid tert-butyl ester (14) as a cream solid.

Provenance & Evidence