Non-d.sup.0 rhenium(V) alkylidyne catalysts useful for catalyzing alkyne metathesis reactions, such as homo- and cross-metathesis of alkynes or diynes, ring closing metathesis and ring-opening metathesis, methods or use, and preparation thereof. The catalysts are stable to air and moisture and tolerate a variety of functional groups in substrates.

The invention relates to a process for preparing 1,3-butadiene by means of ene-yne metathesis over at least one transition metal catalyst of the element ruthenium.

The present invention relates to the use of Ru and Os carbene complexes with a hydroxamic acid (ester) function for the metathesis degradation of nitrile rubber (NBR). The invention further relates to a method for producing hydrogenated nitrile rubbers, by subjecting a nitrile rubber to a metathesis degradation in the presence of the said catalyst, and the degraded nitrile rubber obtained subsequently undergoes a hydrogenation, preferably in situ.

Non-d.sup.0 rhenium(V) alkylidyne catalysts useful for catalyzing alkyne metathesis reactions, such as homo- and cross-metathesis of alkynes or diynes, ring closing metathesis and ring-opening metathesis, methods or use, and preparation thereof. The catalysts are stable to air and moisture and tolerate a variety of functional groups in substrates.

This invention relates generally to the synthesis of E-macrocycles using stereoretentive ruthenium olefin metathesis catalysts supported by dithioiate ligands. Macrocycles were generated with excellent selectivity (>99% E) and in moderate to high/good yields (47% to 80% yield; 58% to 80% yield) from diene starting materials bearing two E-olefins or bearing one E-olefin and one terminal olefin, A variety of rings were constructed, ranging from 12- to 18-membered macrocycles, including the antibiotic recifeiolide. The invention has utility in the fields of organometallics and organic synthesis.

[Problem] To provide a novel artificial protein catalyst that enables the protection of a catalyst from substances in vivo and has potential usefulness in therapeutic in vivo synthetic chemistry.

[Solution] Provided is a complex of a protein and a catalyst selected from a metal catalyst or organic catalyst. In the complex according to the present invention, the protein is a protein having a hydrophobic pocket in the three-dimensional structure thereof, and the catalyst is housed in the hydrophobic pocket so that the catalyst is not or substantially not exposed to a hydrophilic environment.

The present invention relates to the use of Ru and Os carbene complexes with a hydroxamic acid (ester) function for the metathesis degradation of nitrile rubber (NBR). The invention further relates to a method for producing hydrogenated nitrile rubbers, by subjecting a nitrile rubber to a metathesis degradation in the presence of the said catalyst, and the degraded nitrile rubber obtained subsequently undergoes a hydrogenation, preferably in situ.

This invention relates generally to the synthesis of E-macrocycles using stereoretentive ruthenium olefin metathesis catalysts supported by dithioiate ligands. Macrocycles were generated with excellent selectivity (>99% E) and in moderate to high/good yields (47% to 80% yield; 58% to 80% yield) from diene starting materials bearing two E-olefins or bearing one E-olefin and one terminal olefin, A variety of rings were constructed, ranging from 12- to 18-membered macrocycles, including the antibiotic recifeiolide. The invention has utility in the fields of organometallics and organic synthesis.

The invention relates to a process for preparing 1,3-butadiene by means of ene-yne metathesis over at least one transition metal catalyst of the element ruthenium.

Provided herein are compounds that can be used as a catalyst to form cyclic polymers, and methods of making and using the same. For example, provided herein are compounds of formula (I), and formula (1-dimer).

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