Syntheses are described for the preparation of a variety of diynes which are converted to high molecular weight substituted arylenebuta-1, 3-diynylene polymers by oxidative coupling and to high molecular weight substituted arylene-ethynylene polymers by Pd (II) catalysed cross coupling reactions. The products tend to be insoluble in normal organic solvents. Doping with ferric chloride produces significant changes in conductivity but these ...