Ruthenium complex catalyzed polymerization of OH or COOH group containing alkynes to give functionalized poly(acetylene)s

The ruthenium(III) complex (Cp*)RuCl₂]₂ (Cp*=permethylcyclopentadienyl) catalyzes polymerization of propiolic acid to give a mixture of poly(propiolic acid), ---CH=C(COOH)---]_n (1), and cyclic trimers, 1,2,4- and 1,3,5- benzenetricarboxylic acids. GPC analysis shows MN and MW values of the polymer of 4.0 × 10³ and 4.3 × 10³, respectively. Reaction of propiolic acid in the presence of the Ru(II) complex, (Cp*)RuCI(L) (L=1,5-cyclooctadiene and norbornadiene), gives the cyclic trimers rather than 1. (Cp*)RuCl₂]₂ catalyzes polymerization of acetylenedicarboxylic acid and of propargyl alcohol to give the corresponding poly(acetylene) derivatives, ---C(COOH)=C(COOH)---]_n (2) and ---CH=C(CH₂OH)---]_n (3), respectively. Polymerization of ethyl propiolate, 2-butyn-1,4-diol, phenylacetylene and (trimethylsilyl)acetylene using (Cp*)RuCl₂]₂ gives the corresponding polymers ---CH=C(COOEt)---]_n (4), ---C(CH₂OH)=C(CH₂OH)---]_n (5), ---CH=CPh---]_n (6) and ---CH=C(SiMe₃)---]_n (7) in low yields.