This invention relates to novel catalyst compositions based on Ruthenium- or Osmium-based complex catalysts and to a process for selectively hydrogenating nitrile rubbers in the presence of such catalyst compositions.

The present application discloses novel amino-sulfide metal catalysts for organic chemical syntheses including hydrogenation (reduction) of unsaturated compounds or dehydrogenation of substrates. The range of hydrogenation substrate compounds includes esters, lactones, oils and fats, resulting in alcohols, diols, and triols as reaction products. The catalysts of current application can be used to catalyze a hydrogenation reaction under solvent free conditions. The present catalysts also allow the hydrogenation to proceed without added base, and it can be used in place of the conventional reduction methods employing hydrides of the main-group elements. Furthermore, the catalysts of the present application can catalyze a dehydrogenation reaction under homogenous and/or acceptorless conditions. As such, the catalysts provided herein can be useful in substantially reducing cost and improving the environmental profile of manufacturing processes for a variety of chemicals.

Synthetic methods for the in-situ formation of olefin metathesis catalysts are disclosed, as well as the use of such catalysts in metathesis reactions of olefins and olefin compounds. In one aspect, a method is provided for synthesizing an organometallic compound of the formula

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comprising contacting a precursor compound of the formula (X.sup.1X.sup.2ML.sub.jL.sup.1.sub.kL.sup.3.sub.m).sub.i with an acetylenic compound comprising a chelating moiety, optionally, in the presence of a neutral electron donor, wherein M is a Group 8 transition metal, L, L.sup.1, L.sup.2, and L.sup.3 are neutral electron donors, X.sup.1 and X.sup.2 are anionic ligands, j is 1, 2, or 3; k is zero, 1, or 2; m is zero or 1; n is 1 or 2; and i is an integer; with the proviso that k is zero when the precursor compound is contacted with the acetylenic compound in the presence of the neutral electron donor, and R.sup.1 and R.sup.2 are independently selected from hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, substituted heteroatom-containing hydrocarbyl, and functional groups, wherein R.sup.1 and R.sup.2 are linked and together form one or more cyclic groups, R.sup.2 and L.sup.2 are linked and together form one or more cyclic groups, and any other two or more of X.sup.1, X.sup.2, L.sup.1, L.sup.2, L.sup.3, R.sup.1, and R.sup.2 can be taken together to form one or more cyclic groups. The invention has utility in the fields of catalysis, organic synthesis, polymer chemistry, and industrial and fine chemicals chemistry.