Tetranuclear ruthenium clusters

As previous studies by Ford32 had suggested that both tri and tetranuclear ruthenium clusters were important for the catalysis, Shore et al.64 tested the decomposition rate of H3Ru4(CO)12 , and samples were examined by H NMR... 

A relatively simple example of this class of cluster catalysis is the hydrogenation of ethylene catalyzed by the tetranuclear ruthenium cluster H4Ru4(CO)i2 described by the following equations. 

Submitted by MICHAEL 1. BRUCE and MICHAEL L. WILLIAMS Checked by GUY LAVIGNE and TH RESE ARLIGUIEt This tetranuclear ruthenium carbonyl hydride was described on several occasions,5 but early preparations were usually contaminated with Ru3(CO)12, giving rise to suggestions of the existence of two isomeric forms. The situation was clarified by the work of Kaesz and coworkers,6 who discovered the direct route from Ru3(CO)12 and hydrogen, which is described below. The compound is often obtained from reactions between Ru3(CO)12 and substrates containing hydrogen (hydrocarbons, ethers, alcohols, water, etc.) and by acidification of anionic ruthenium cluster carbonyls.7... 

TRI- AND TETRANUCLEAR CARBONYL-RUTHENIUM CLUSTER COMPLEXES CONTAINING ISOCYANIDE, TERTIARY PHOSPHINE, AND PHOSPHITE LIGANDS. RADICAL ION-INITIATED SUBSTITUTION OF METAL CLUSTER CARBONYL COMPLEXES UNDER MILD CONDITIONS... 

Inorganic Syntheses, Volume 26 Edited by Herbert D. Kaesz Copyright 1989 by Inorganic Syntheses, Inc. Tri- and Tetranuclear Carbonyl-Ruthenium Cluster Complexes 271... 

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