Methyl 4-aminobenzoate → 4-(5-Bromoimidazo[1,2-a]pyrazin-8-ylamino)benzoic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

A mixture of 5,8-dibromoimidazo[1,2-a]pyrazine (2 g, 7.3 mmol), 4-amino benzoic acid methyl ester (0.93 g, 6.2 mmol), NaOtBu (0.98 g, 10.2 mmol), Pd2(dba)3 (133 mg, 0.14 mmol), Xantphos (168 mg, 0.29 mmol) and toluene is degassed with nitrogen, then heated at 85° C. for 18 hours. The toluene is removed in vacuo, then MeOH is added to the crude residue. The solid is collected by filtration and dried in the vacuum oven. The solid is identified as the desired title ester. The filtrate is chromatographed with petrol:EtOAc (70:30 followed by 50:50) and the fractions containing the desired product, combined, evaporated and triturated with MeOH. The resultant solid is collected by filtration and is also identified as the desired ester.

Provenance & Evidence