Synthesis of Ultra-High-Molecular-Weight Aromatic Polyacetylenes with [Rh(norbornadiene)Cl]2-Triethylamine and Solvent-Induced Crystallization of the Obtained Amorphous Polyacetylenes

Substituted polyacetylenes

“…The selective formation of cis-transoidal structure was confirmed by Furlani and Feast using 1 H and 13 C NMR, 58 and it was found by Tabata that Et 3 N works as an effective cocatalyst in the [(nbd)RhCl] 2 -catalyzed (nbd: 2,5-norbornadiene) polymerization. 59 The features of Rh catalysts as compared with group 5 and 6 metathesis catalysts include cis-transoidal structure of the formed polymer, tolerance to polar moieties in the monomer and to polar solvents, and restriction of the kinds of monomers to monosubstituted acetylenes. It is interesting to note that Rh-catalyzed polymerization proceeds even in water.…”

Pressure-inducedcis totrans isomerization of aromatic polyacetylenes prepared using a Rh complex catalyst: A control of ?-conjugation length

“…2 It has been proposed that the effect of the solvents is to promote In a previous article we reported that phenylacetthe efficient dissociation of the dimer complex ylene (PA), 1 its homologues, 2 a-naphthylacety-[Rh(NBD)Cl] 2 into the monomeric species, which lene, 3 and alkylpropiolates, 4,5 and pentynoate 6 may be an important initiation species for this can be stereospecifically polymerized in the prespolymerization, 1,7 as shown in Scheme 1. Further, ence of a Rh complex, [Rh(norbornadiene)Cl] 2 , the structural differences observed between poly-[Rh(NBD)Cl] 2 , when triethylamine (TEA) or an pentynoates prepared with the Rh complex cataalcohol is used as the polymerization solvent and lyst and with metathesis catalysts such as WCl 6 that the helical cis-transoid isomer were selecwas interpreted in terms of the difference in geotively formed in high yields under mild conditions. metrical structures, i.e., the Rh complex 5 selecIn addition, we have shown that the Rh complex tively produced the cis-transoid polymer and the is the preferred catalyst for the living polymerizametathesis catalyst gave the trans-transoid form as the major component.…”

Synthesis and Properties of Liquid-Crystalline-Conjugated Polymers

“…Polymerizations of PCHn03A and BP503A were carried out by using a ZieglerNatta catalyst, 19 Fe(acac) 3 -AlEt 3 , and a metathesis catalyst, 20 MoCl 5 -Ph 4 Sn, in toluene for 21 h at room temperature. For some of the monomers, a chlorine-bridged rhodium complex, 21 [Rh(NBD)Cl] 2 , was used with NEt 3 as a co-catalyst, and the polymerization time was within 6 min at room temperature. 4f-g The polymerizations were terminated by pouring the reaction mixture into a large amount of methanol.…”