Synthesis, characterization, and reactivity of a novel ruthenium carbonyl cluster containing tri-O-benzyl-d-glucal as a chiral carbohydrate ligand

A chiral carbohydrate ligand 3,4,6-tri-O-benzyl-d-glucal (L) reacts with the cluster triruthenium dodecacarbonyl Ru3(CO)12 giving a novel chiral cluster Ru3(μ-H)2(CO)9(L-2H) (I) that shows fluxional behavior at room temperature. The reaction of Ru3(μ-H)2(CO)9(L-2H) (I) with triphenylphosphine and diphenylphosphinoethane (dppe) gives two new clusters Ru3(μ-H)2(CO)7(L-2H)(PPh3)2 (II) and Ru3(μ-H)2(CO)7(L-2H)(dppe) (III). The new compounds I, II and III have been characterized by a combination of elemental analysis, mass spectrometry, infrared and variable temperature NMR spectroscopy.