Synthesis and characterization of a series of rhodium, iridium, and ruthenium isocyanide complexes

Several new electrophilic metal isocyanide complexes have been fully characterized and reported herein. Isocyanide induced cleavage of the dimer, [LMCl2]2 {LM = Cp∗Ir, Cp∗Rh, or (p-cymene)Ru}, with 2,6-xylylisocyanide or 2,6-diethylphenylisocyanide produces complexes of the general formula LM(CNAr)Cl2. Halide metathesis of the dichloro complexes with sodium iodide produces the corresponding complexes with the general formula LM(CNAr)I2. For the analogous ruthenium complexes better results were achieved via isocyanide induced cleavage of [(p-cymene)RuI2]2 and was synthesized differently from previous reports. Several neutral complexes in reaction with AgPF6 in acetonitrile form cationic, solvent-coordinated complexes have been fully characterized. Most reactions with rhodium decomposed to either [Cp∗RhCl(MeCN)]2[(PF6)2] starting from the dichloro complexes, or [Cp∗Rh(MeCN)3,(PF6)2] and Cp∗Rh(CNAr)I2 starting from the diiodo complexes. Several bases were probed to see if cyclization could be induced, but were not successful in any case. Many of these complexes have been characterized by single crystal X-ray crystallography.