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The reactions of Ru 3 (CO) 12 with oximes of α-substituted caran 4 one, lemonen 5 and pinan 3 one derivatives were studied. The reactions at elevated temperatures yield binu clear complexes Ru 2 (CO) 4 L 2, with two ruthenium atoms bridging two terpenoid ligands (L) through the oxime groups and coordinated additionally to a nitrogen or sulfur atom of the NR 2 or SR groups respectively. The reactions carried out at room temperature in the presense of Me 3 NO yield trinuclear complexes Ru 3 (CO) 8 L 2 with analogous coordination of the terpenoid ligands. In a solution at room temperature these clusters readily transform to binuclear complexes. The NMR spectroscopy shows the stereochemical nonrigidity of the complexes with the S-CH 2 -Ph fragment: at room temperature in a solution the benzyl radical undergoes slow rotation about the S-C bond and a change of the conformation of carane and pinane carbocycles occurs more rapidly. The reactions with pinane and carane derivatives are stereospecific yielding only one of the possible diastereoisomers. More flexible limonene derivative form both diastereoisomers.One of the most promising directions in the chemistry of ruthenium carbonyl complexes is their use in catalysis. In the past decade, a number of reports have been pub lished concerned with the catalytic processes involving ruthenium carbonyl clusters as the active species. In the majority of cases, the reactions studied are hydrogena tion, 1 hydroformylation, 2 and isomerization 3 of unsatur ated organic compounds. The efficiency of a catalytic pro cess involving a metal complex is determined by the abili ty of formation in such a catalyst of a free coordination site. For cluster complexes, this could be achieved by breaking the metal metal bond or by the introduction of a labile ligand to the complex. The use of complexes with "hemilabile" ligands, i.e., polydentate heterofunctional ligands having one functional group capable of reversible decoordination seems to be the most promising in cataly sis. This approach was successfully used for mononuclear complexes, 4 but synthesis and use of clusters with hemi labile ligands is much less studied so far. 5From the viewpoint of preparing carbonyl cluster com plexes with hemilabile ligands, we were interested in ste reochemically rigid α substituted oximes 1-7 of the terpene series, the use of which also allows investi gating the influence of stereochemical factors on their reactions with ruthenium carbonyl clusters and on the properties of the resulting complexes. The mononucle ar complexes of oximes are reasonably well studied due to their biological activity and structural diversity. 6 Reac tions of oximes with carbonyl cluster complexes are studied to a lesser extent. Several papers have been published on the chemistry of osmium trinuclear clus ters 7,8 and only one report 9 concerned the reaction of Ru 3 (CO) 12 with oximes. X = NH 2 (1), NHMe (2), NMe 2 (3, 5), SCH 2 Ph (4, 6) Results and DiscussionTwo methods were used for substitution of CO in Ru 3 (CO) 12 , viz, ...

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