example 1 were repeated except cu i cl was replaced with cu i br the product was analyzed by gas chromatography and the conversion ratio the selectivity and the yield were calculated the results were shown in table 2 the procedures of example 8 were repeated except 2 methylimidazole was replaced with n acetylimidazole the product was analyzed by gas chromatography and the conversion ratio the selectivity and the yield were calculated the results were shown in table 2 the procedures of example 1 were repeated except the reaction system was pressured with nitrogen gas to 20 kg cm 2 the product was analyzed by gas chromatography and the conversion ratio the selectivity and the yield were calculated the results were shown in table 3 the procedures of example 1 were repeated except the reaction system was pressured with nitrogen gas to 30 kg cm 2 the product was analyzed by gas chromatography and the conversion ratio the selectivity and the yield were calculated the results were shown in table 3 the procedures of example 1 were repeated except the amount calculated as cu of cu i cl was changed to 10000 ppm the product was analyzed by gas chromatography and the conversion ratio the selectivity and the yield were.