Synthesis and structure of some ruthenium–rhenium heterodinuclear complexes and their catalytic activity in the addition of carboxylic acids to phenylacetylene

The salt elimination reaction of Na[Re(CO)5] with Cp*Ru(dppm)Cl, CpRu(dppm)Cl or CpRu(CO)2Cl afforded the heterodinuclear species Cp*Ru(μ-CO)2(μ-dppm)Re(CO)3, Cp(CO)Ru(μ-dppm)Re(CO)4, or Cp(CO)2RuRe(CO)5, respectively, in moderate yields. An orthometallated species, Cp*(CO)Ru(μ-H)[μ-PhP(C6H4)CH2PPh2]Re(CO)3, was also obtained from the first reaction. All these heterodinuclear products have been characterised crystallographically. They also showed good catalytic activity for the addition of carboxylic acids to phenylacetylene to afford the anti-Markovnikov products selectively.