Simple Synthesis of alfa, omega-Diarylpolyynes Part 1: Diphenylpolyynes

Aseries of ?, ?-diphenylpolyynes were synthesized through the Cadiot Chodkiewicz reaction starting fromCu(I)-phenylacetylide and diiodoacetylene. The complete series of diphenylpolyynes -(C C)n- with n = 2,3,4 and 5 was obtained and analyzed by electronic absorption spectroscopy, liquid chromatography (HPLC-diode array) and FT-IR spectroscopy. The diphenylpolyynes when treated with nascent hydrogen produced by the action of HCl on Zn dust are changed into a mixture of diphenylpolyenes as shown by UV spectroscopy and HPLC.