Triruthenium and Triosmium Carbonyl Cluster Complexes Containing Bridging Ligands Derived from 2-Amino-7,8-benzoquinoline

Abstract

The ruthenium cluster complexes [Ru 3 (μ 3 -η 3 -abq-C,N,N)(CO) 9 ] (1) and [Ru 3 (μ-H) 2 (μ 3 -η 3 -abq-C,N,N) 2 (CO) 6 ] (2) (H 2 abq = 2-amino-7,8-benzoquinoline) have been stepwise prepared from [Ru 3 (CO) 1 0 (MeCN) 2 ]. Both compounds contain cyclometalated abq ligands which span a Ru-Ru edge through the N atom of an amido fragment and chelate the remaining Ru atom through both the quinolinic N atom and the C atom of the cyclometalated ring. For steric reasons, the cyclometalation is responsible for the observation of short Ru-N a m i d o bond lengths. The reaction of the osmium cluster [Os 3 (CO) 1 0 (MeCN) 2 ] with H 2 -abq gives the amido-bridged decacarbonyl derivative [Os 3 (μ-H)(μ-η 1 -Habq-N)(CO) 1 0 ] (3). Curiously, while complex 3 is stable in refluxing toluene, the ruthenium analogue of 3 has not been detected. Compounds 1-3 represent the first trinuclear carbonyl clusters containing ligands derived from 2-amino-7,8-benzoquinoline.