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A linear codimerization of 2-norbornenes with acrylic compounds such as acrylates and an acrylamide proceeded efficiently by ruthenium catalyst systems to afford the corresponding exo-trans-2-norbornylacrylates as major products regio- and stereoselectively along with a small amount of cis isomers. The obtained codimers are potentially expected as monomers with a bulky substituent for materials such as high-resolution photoregists.

Recent advances in the chemistry of transition metal-catalyzed organosulfur compounds containing carbon-sulfur bonds are reviewed here. A description of the novel reactions in this field such as reaction of halides with sulfur-containing compounds, allylic sulfide synthesis, addition of thiols to alkynes, alkenes, and allenes is presented.

The yields of mono- and di-alkylated amines vary with the type of ruthenium complexes used as catalysts during the N-alkylation of heteroaromatic amines with alcohols. 2-aminopyridine reacts with excess of ethanol at 180 degrees celsius for 20 hours to give 9% 2-(ethylamino)pyridine (1) and 70% 2-(diethylamino)pyridine with dichlorotris(triphenylphosphine)ruthenium as catalyst. The use of (eta(super 4)-1,5-cyclooctadiene)(eta(super 6)-1,3,5-cyclooctatriene)ruthenium as catalyst forms 85% of 1 even in excess of ethanol. The use of tertiary phosphines and phosphites increases the dialkylated form.

A ruthenium complex, Ru3(CO)12/1, 10-phenanthroline catalyzes the carbonylation of allylic alkyl carbonates producing alpha,beta- or beta,gamma-unsaturated esters in good yields. Pressure of carbon monoxide influences the regioselectivity of the carbonylation of crotyl methyl carbonate. Reaction at 20-50 atm facilitates the carbonylation of the more sterically hindered carbon. Carbonylation of cinnamyl methyl carbonate in the absence of 1,10-phenanthroline and at high temperatures produces a dimer, dimethyl 3-benzyl-2-(trans-2-phenylvinyl)glutarate.

Simple and readily available ruthenium complexes of the type CpRuCIL(sub 2) are found to act as efficient catalysts for the synthesis of propargylic sulfides through S-propargylation of aromatic or aliphatic thiols under neutral conditions. This reaction may complement the previously reported thiolate-bridged diruthenium complex-catalyzed S-propargylation of thiols with terminal propargylic alcohols.

A novel and rapid ruthenium-catalyzed synthesis of pyranopyrandiones by the reconstructive carbonylation of cyclopropenones is developed. All pyranopyrandiones prepared in this study are new compounds, which are quite attractive as novel functional monomers due to their characteristic physical and chemical properties.

The first catalytic intermolecular [2@!] cocyclization of alkynes, isocyanates and CO is developed. This methodology has provided a rapid and atom-economical method for the synthesis of a variety of unsymmetrically polysubstituted maleimides in one step.

A study on the catalyst system of [RuCl2(CO) 3]2/(1,3-bis(diphenylphosphino)propane) when used concomitantly with K2CO3 and allyl acetate in N-methylpiperidine is highly effective for the direct synthesis of cyclic imines from general aminoalkenes. The process provides an effective method for the catalytic synthesis of unsaturated nitrogen heterocycles like 1-pyrroline and indole derivatives without the use of expensive aminoalkynes.

A new enantioselective allylic amination and alkylation catalyzed by planar-chiral cyclopentadienyl-ruthenium complexes is described. The reports indicate that this is not only the first successful ruthenium-catalyzed asymmetric allylic amination and alkylation, but also the first asymmetric catalysis of planar-chiral complexes of late transition metals.

Research is presented concerning the use of cyclobutenediones to construct multicyclic compounds. The activation of carbon-carbon bonds by transition-metal complexes in cyclobutenediones is discussed.

Results of a study demonstrated the first transition-metal complex catalyzed addition of organic disulfides to alkenes which enables the rapid synthesis of vicinal-dithioethers. This catalytic system was found to be practical and useful for the formation of vicinal-dithioethers from organic disulfides and alkenes. It was concluded that this discovery will ne helpful in transition-metal catalyzed sulfur chemistry, since organosulfur compounds are useful intermediates in organic synthesis.

A study was conducted on ruthenium-catalyzed Beta-allyl elimination. The findings demonstrate the possibility of developing the first and practical ruthenium-catalyzed deallylation of tertiary homoallyl alcohols via selective cleavage of a C-C bond. Moreover, the results suggest that this C-C bond cleavage involves the first Beta-alkyl elimination from an (alkoxy)-ruthenium intermediate in its catalytic cycle.

The first ever ruthenium-catalyzed intramolecular Pauson-Khand reaction has been formulated. In the past, much attention has been lavished on catalytic systems involving cobalt and titanium catalysts. An experiment takes past studies one step further by inserting carbon monoxide into ruthenacyclopentene, which results in a catalytic version of the Pauson-Khand reaction. This reaction being very powerful, this catalytic process could be a highly useful instrument in the study of organic synthesis.

The synthesis of 1-pyrroline derivatives from gamma-nitrocarbonyl compounds is presented. The synthesis involves the transition-metal complex-catalyzed N-heterocyclization of nitroarenes by carbon monoxide. The reaction was adapted to aliphatic nitro compounds by using a Ru3(CO)12/1,10-phenanthroline system.