Cyclopolymerization of terminal 1,6-diacetylenes

Poly(1,6-heptadiyne)-Based Materials by Metathesis Polymerization

“…Various dipropargyl derivatives carrying heteroatoms at the 4-position of 1,6-heptadiyne has been synthesized and polymerized by transition metal catalysts (Table ). The polymerization of dipropargyl ether (DPE) by MoCl 5 alone proceeded well to give a quantitative yield of a polymer. , WCl 6 -based catalysts, which had been known to be very effective for the polymerization of some monosubstituted acetylenes such as phenylacetylene, , 2-ethynylthiophene, and 2-ethynylpyridine, were found to be less effective for this polymerization (yield ≤ 52%). Poly(dipropargyl sulfide) was prepared in a yield of 91% using the WCl 6 −EtAlCl 2 catalyst system.…”

“…Poly(diphenyldipropargylmethane) (DPDPM) was completely soluble in aromatic hydrocarbons (benzene, toluene, xylene) and halogenated hydrocarbons (CCl 4 , CHCl 3 , CH 2 Cl 2 , chlorobenzene), but insoluble in ethyl ether, aliphatic hydrocarbons, and alcohols. Poly(dipropargyl ether) and poly(dipropargyl sulfide), which are very similar to poly(1,6-heptadiyne), were also insoluble in any organic solvents. , However, similar homologues, poly(dipropargyl sulfoxide) and poly(dipropargyl sulfone), were soluble in DMF and DMSO. , It was assummed that the ideal linear conjugated polymers were mainly obtained by the increased cyclopolymerization probability as the oxidation state of sulfur is increased . In most cases, the poly(1,6-heptadiyne)s having substituents were soluble and easily solution castable…”

“…Poly(dipropargyl ether) and poly(dipropargyl sulfide), which are very similar to poly(1,6-heptadiyne), were also insoluble in any organic solvents. 202,203 However, similar homologues, poly(dipropargyl sulfoxide) and poly(dipropargyl sulfone), were soluble in DMF and DMSO. 204,205 It was assummed that the ideal linear conjugated polymers were mainly obtained by the increased cyclopolymerization probability as the oxidation state of sulfur is increased.…”