Nitrile ligands for controlled synthesis of alkynyl-ruthenium based homo and hetero bimetallic systems

Wire like mono- and poly-nuclear molecules based on alkynyl ruthenium complexes whose core unit is traps-[Ru(C equivalent to CR)(R'C equivalent to N)(dppe)(2)][PF(6)] are readily formed in soft conditions. The electronic dual character of the metallic unit, donor through the acetylide moiety, acceptor versus the nitrile ligand is exemplified through electrochemical studies of a series of ethynylferrocene and cyanoferrocene derivatives. A single crystal X-ray diffraction analysis of the [(dppe)(2)(PhC equivalent to C)Ru(N equivalent to C-C(6)H(4)-C equivalent to N)Ru(C equivalent to CPh)(dppe)(2)][2PF(6)] bimetallic complex 5 shows that the global structure of such complexes consists of wire type dimetallic units. With the availability of this versatile, direct, and simple route, a new class of extended rigid rod systems of nanometric size with multilevel electron transfers is readily accessed. (c) 2006 Elsevier B.V. All rights reserved.