Triethylamine → Tert-butyl-[2-(5-phenylethynyl-thiophen-2-yl)-imidazo[1,2-a]pyrazin-3-yl]-amine

Participants

Reaction Conditions

Reaction Steps

420 mg (1.2 mmol) of [2-(5-bromothiophen-2-yl)-imidazo[1,2-a]pyrazin-3-yl]-tert-butyl-amine were dissolved together with 0.33 ml (3.0 mmol) of phenylacetylene, 42 mg (0.06 mmol) of bis(triphenylphosphine)-palladium(II) chloride and 22 mg (0.12 mmol) of copper(I) iodide in DMF (9 ml). After addition of 1.6 ml (12.0 mmol) of triethylamine, the mixture was stirred at 50° C. for 16 h. The reaction solution was then diluted with EA and combined with a sat. aq. sodium carbonate solution. The phases were separated and the aqueous phase extracted with EA. The combined organic phases were washed 2× with a sat. aq. sodium carbonate solution and 2× with a sat. aq. common salt solution and dried over magnesium sulfate. After filtration and removal of the solvents under a vacuum, column chromatography (EA/DCM 1:4) was carried out with the group, after which 326 mg (0.88 mmol, 73% of theoretical) of tert-butyl-[2-(5-phenylethynyl-thiophen-2-yl)-imidazo[1,2-a]pyrazin-3-yl]-amine were obtained.

Provenance & Evidence