SynopsisThe catalytic activity of a series of [Rh L-L chel]X complexes, in which we have varied the unsaturated ligand [L-L = cis, cis-cycloocta 1,5-diene(cod) or 2,5-norbornadiene(nbd)] the nitrogen chelating ligand [chel = 2,2'-bipyridine(bipy), 2,2'-dipyridylamine(dipyam), 2,2'-bipyrazine (bipz), 4,4'-dimethyl-2,2'-bipyridine (4,4'-Mqbipy)] and the counter ion [X = PF,, ClO,, BPh,], has been examined in reactions with phyenylacetylene (PA). The catalytic behaviour of t h e [Rh(cod)Cl,],tmeda] (tmeda = N,N,N',N'tetramethylethylendiamine), [Rh(cod)Cl,],teda] (teda = triethylendiamine), of the dimer [Rh(cod)Cl],, and the use of NaOH as cocatalyst in different reaction conditions was also examined. The influence of the ligands on the catalytic activity of these Rhl complexes is discussed. 'H and 13C NMR spectra have shown that highly stereoregular polyphenylacetilene can be obtained. Conditions for homogeneous doping of PPA, to obtain materials whose conductivity varies over 10-11 magnitude orders, are proposed. The stability of the doped polymers is also discussed.

In polymerization reactions of phenylacetylene three different types of polyphenylacetylene (PPA) were prepared by using Rh and Pt complexes as catalysts in different reaction conditions. Type I PPA is obtained with [Rh (COD) Chel] PF6 complexes (COD = cis,cis‐cycloocta 1,5‐diene; chel = 2,2′‐bipyridine, 1,10‐phenanthroline, 2,9‐dimethyl‐1,10‐phenanthroline, 5,6‐dimethyl‐1,10‐phenanthroline, 3,4,7,8‐tetramethyl‐1,10‐phenanthroline) in bulk, benzene methanol, while type II PPA is obtained with the same catalysts in p‐dioxane and type III PPA in the presence of [Pt (CCPh)2(PPh3)2] in bulk. Type I, II, and III PPA exhibit different IR and 1H‐NMR spectra, which have been compared with literature data. Correlations proposed by different Authors between spectral properties of PPA and chain structures are also discussed.

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