Firstly, a mixture of 5,5′-dibromo-2,2′-bipyridyl (300 mg, 0.96 mmol), PdCl2(PPh3)2 (60 mg, 0.085 mmol) and CuI (30 mg, 0.16 mmol) was added with dist. THF (18 mL), dist. i-Pr2NH (2.4 mL) and trimethylsilylacetylene (467 μL, 3.3 mmol). The resultant mixture was then stirred under a nitrogen atmosphere at room temperature for 29 hours to obtain a reaction mixture. Subsequently, a salt contained in the reaction mixture was removed through a celite filtration process. The organic layer thus obtained was concentrated to obtain a crude product (I) Then, the obtained crude product (I) was separated and purified by silica gel column chromatography (CH2Cl2=100) to obtain 5,5′-bis(trimethylsilylethynyl)-2,2′-bipyridyl.
