Ethanol → Tert-butyl 5-(2,4-dichlorophenyl)-7-methyl-2-(5-methyl-1,2,4-oxadiazol-3-yl)imidazo[1,2-a]pyrimidine-6-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of tert-butyl 2-cyano-5-(2,4-dichlorophenyl)-7-methylimidazo[1,2-a]pyrimidine-6-carboxylate (50 mg, 0.12 mmol) in EtOH (3 mL) was added NH2OH.HCl (10 mg, 0.12 mmol) and KOH (8.5 mg, 0.12 mmol). After heating to 70° C. for 6 h, the reaction was concentrated under reduced pressure. The resulting residue was suspended in H2O and filtered to collect the desired product as a yellow solid (53 mg). This product was dissolved in PhCH3 (3 mL) and DMA-DMA (0.2 mL) was added. The reaction was heated to 90° C. for 2 h and was concentrated and purified by silica gel chromatography to give tert-butyl 5-(2,4-dichlorophenyl)-7-methyl-2-(5-methyl-1,2,4-oxadiazol-3-yl)imidazo[1,2-a]pyrimidine-6-carboxylate (46 mg, 68% for three steps) as a light yellow solid.

Provenance & Evidence