Piperidine → 6-ethynyl-N-phenylimidazo[1,2-a]pyridine-2-carboxamide

Participants

Reaction Conditions

Reaction Steps

0.2 g of 6-iodo-N-phenylimidazo[1,2-a]pyridine-2-carboxamide, 156 μl of trimethylsilylacetylene, 20 mg of dichlorobis(triphenylphosphine)palladium and 2 ml of piperidine are charged to a 20 ml microwave tube. The mixture is heated for 15 minutes in the microwave device adjusted to 130° C. After cooling, the mixture is poured into 50 ml of a saturated aqueous ammonium chloride solution. Extraction is carried out twice with 70 ml of ethyl ether. The combined organic phases are separated by settling, dried and concentrated to dryness under reduced pressure. The residue is taken up in 4 ml of a 1M solution of tetrabutylammonium fluoride in THF and stirred at 25° C. for 16 hours. After evaporating the reaction medium to dryness, the residue is chromatographed on silica, elution being carried out with a mixture of cyclohexane and ethyl acetate (gradient from 0 to 35%), to give 30 mg of 6-ethynyl-N-phenylimidazo[1,2-a]pyridine-2-carboxamide in the form of a beige solid.

Provenance & Evidence