Synthesis and characterization of new difunctional alkynylated (η6-arene)(η4-cycloocta-1,5-diene)ruthenium(0) complexes as molecular models for organometallic polymers

The new dialkynylated complexes Ru(η6-DEB-Si)(η4-COD), 4a, Ru(η6-DEBP-Si)(η4-COD), 4b1, Ru2(η6,η6-DEBP)(η4-COD)2, 4b2 [COD = 1,5-cyclooctadiene; DEB-Si = 1,4-bis(trimethylsilylethynyl)benzene; DEBP-Si = 4,4′-bis(trimethylsilylethynyl)biphenyl] have been synthesized by the arene exchange reaction with the complex Ru(η6-naphthalene)(η4-COD). The complexes Ru(η6-DEB)(η4-COD), 5a, and Ru(η6-DEBP)(η4-COD), 5b1, have been prepared by desilylation of the corresponding compounds 4a and 4b1. All the complexes have been fully characterized by means of spectroscopic techniques.