Cyclopolymerization of 4,4-diphenoxy-1,6-heptadiyne by transition metal catalysts

Abstract

4,4-diphenoxy-1,6-heptadiyne was prepared by a Grignard reagent of propargyl bromide with dichloro-diphenoxy methane. Polymerization was attempted by MoCl$_5$ and WCl$_6$ associated with coatalyst such as organotin and organoaluminium compounds. A moiybdenium catalyst was found to be a particularly effective catalyst for the cyclopolymerization of 4,4-diphenoxy- 1,6heptadiyne. Polymerization of 4,4-diphenoxy-1,6-heptadiyne by various catalysts leads to a violet solid ($\overline{Mn}=52000$), soluble in common organic solvents. The structure of polymer was identified by $^1$H-NMR, $^{13}$C-NMR, IR and UV-Vis spectroscopies. From these spectroscopic results, poly(DPHD)s possess polyene structures having cyclic recurring units in the polymer backbone. The poly(DPHD) has excellent properties in both the solubility in general organic solvent and the oxidation stability identified from IR spectra. The electrical conductivity is 10$^{-3}$s/cm for I$_2$ doping.