Under an argon atmosphere 49 mg (0.06 mmol) of PdCl2(dppf) and 11 mg (0.06 mmol) of CuI were added to a repeatedly degassed solution of 535 mg (3.30 mmol) of 2-(4-chlorophenyl)-5-iodopyrazine, 950 mg (3.30 mmol) of 2-(4-ethynylphenoxy)ethanol, and 0.59 mL (6.00 mmol) of piperidine in 50 mL of THF and the mixture was stirred for 4 hours at RT. The precipitate was suction filtered and washed with acetonitrile. The mother liquor was concentrated, and the precipitate formed was filtered off and washed with acetonitrile. The precipitates were combined. Yield: 700 mg (67% of theoretical); C20H15ClN2O2 (M=350.798); calc.: molpeak (M+H)+:351/353 (Cl); found: molpeak (M+H)+:351/353 (Cl); Rf value: 0.30 (silica gel, PE/EtOAc 1:1).
