Potassium Phosphate, Tribasic → 8-(4-Bromo-2-chloro-phenylamino)-imidazo[1,5-a]pyridine-7-carboxylic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

A suspension of 8-chloro-imidazo[1,5-a]pyridine-7-carboxylic acid methyl ester (300 mg, 1.43 mmol), 4-bromo-2-chloroaniline (354 mg, 1.72 mmol), Pd2dba3 (65 mg, 0.07 mmol), 2-dicyclohexylphosphino-2′,6′-diisopropoxybiphenyl (131 mg, 0.28 mmol) and K3PO4 (424 mg, 2.00 mmol) in toluene (5 ml) was degassed and then heated at 110° C. for 18 hours. The reaction mixture was then cooled to room temperature and diluted with ethyl acetate. The resultant mixture was washed with water and brine, then loaded onto a 10 g Isolute® SCX-2 cartridge which was eluted with methanol and then a 2M solution of ammonia in methanol. The appropriate fractions were combined and concentrated in vacuo. The resultant residue was subjected to flash chromatography (Si-PPC, gradient 0% to 100%, ethyl actetate in DCM) to afford the title compound as a yellow oil (271 mg, 50%). LCMS (method B): RT=3.65 min, [M+H]+=381/383.

Provenance & Evidence