Disclosed herein is a method for selectively reducing, using electrical energy, CO.sub.2 to carbon monoxide or formic acid, a catalyst for use in the method, and an electrochemical reduction system. The method for producing carbon monoxide or formic acid by electrochemically reducing carbon dioxide of the present invention includes (a) reacting carbon dioxide with a metal complex represented by formula (1), and (b) applying a voltage to a reaction product of the carbon dioxide and the metal complex represented by formula (1):

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A composition containing the following components: (a) a hydrosilylation catalyst comprising a metal-ligand complex, and (b) an inhibitor of the catalyst, wherein the inhibitor differs from the ligand of the metal-ligand complex and is represented by formula (I):

X—CHR—CO—Y  (I),

wherein —X represents —NO.sub.2, —S(═O)R, or R.sup.c.sub.2R.sup.aC—CO—; Y represents 2-furyl, —S(═O)R, —CN, —NO.sub.2, or —CR.sup.b.sub.xR.sup.d.sub.3-x; R.sup.a and R.sup.b is independently selected from the group consisting of —O—R, —O—CO—R, —CO—O—R, 2-furyl, —S(═O)R, —CN, —NO.sub.2, —F, —Cl, and —Br; each of R is independently selected from the group consisting of —H, optionally fluorinated C.sub.1-C.sub.8-alkyl, —F, —Cl, and —Br; each of R.sup.c and each of R.sup.d is independently selected from the group consisting of —H, optionally fluorinated C.sub.1-C.sub.8-alkyl, —F, —Cl, and —Br; and x is 0 or 1.

An improved catalyst for cyclic olefin polymerization. The catalyst includes a transition metal carbene having the following structure: M.sup.v(OR’).sub.c*mX(.sub.v-c*m-2)=C(R*).sub.2 wherein M.sup.v is a Group 5 transition metal having a valence (v) of 5 or a Group 6 transition metal having a valence (v) of 5 or 6; each R′ is independently a monovalent organic moiety comprising from 8 to 40 atoms selected from Groups 14-17; c is an integer from 1 to 3; m is ⅓, ½, 1, 3/2, 2, 3, or 4 and c*m ≤ v-2; X is a halogen; and each R* is independently H or a C.sub.1 to C.sub.7 alkyl. The catalyst is particularly useful for ring-opening metathesis polymerization (ROMP).

Disclosed herein is a method for selectively reducing, using electrical energy, CO.sub.2 to formic acid, a catalyst for use in the method, and an electrochemical reduction system. The method for producing formic acid by electrochemically reducing carbon dioxide of the present invention includes (a) reacting carbon dioxide with a metal complex represented by formula (1), and (b) applying a voltage to a reaction product of the carbon dioxide and the metal complex represented by formula (1):

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The present invention relates to a ligand compound, an organic chromium compound, a catalyst system for ethylene oligomerization, a preparation method thereof, and an ethylene oligomerization method using the same. The catalyst system for ethylene oligomerization according to the present invention is used to prepare a low-density polyethylene in one reactor by using a small amount of comonomers such as alpha-olefin or by using only ethylene without comonomers, because it maintains high catalytic activity and high alpha-olefin selectivity even though supported on a support.

A composition containing the following components: (a) a hydrosilylation catalyst comprising a metal-ligand complex, and (b) an inhibitor of the catalyst, wherein the inhibitor differs from the ligand of the metal-ligand complex and is represented by formula (I):
X—CHR—CO—Y  (I),
wherein —X represents —NO.sub.2, —S(═O)R, or R.sup.c.sub.2R.sup.aC—CO—; Y represents 2-furyl, —S(═O)R, —CN, —NO.sub.2, or —CR.sup.b.sub.xR.sup.d.sub.3-x; R.sup.a and R.sup.b is independently selected from the group consisting of —O—R, —O—CO—R, —CO—O—R, 2-furyl, —S(═O)R, —CN, —NO.sub.2, —F, —Cl, and —Br; each of R is independently selected from the group consisting of —H, optionally fluorinated C.sub.1-C.sub.8-alkyl, —F, —Cl, and —Br; each of R.sup.c and each of R.sup.d is independently selected from the group consisting of —H, optionally fluorinated C.sub.1-C.sub.8-alkyl, —F, —Cl, and —Br; and x is 0 or 1.

The various embodiments provide, a magnesium titanium polymerization procatalyst, and methods for making and using the same.

Disclosed herein is a method for selectively reducing, using electrical energy, CO.sub.2 to carbon monoxide, a catalyst for use in the method, and an electrochemical reduction system. The method for producing carbon monoxide by electrochemically reducing carbon dioxide of the present invention includes (a) reacting carbon dioxide with a metal complex represented by formula (1), and (b) applying a voltage to a reaction product of the carbon dioxide and the metal complex represented by formula (1):

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A catalyst system has been designed that disrupts the sedimentation process. The catalyst system achieves this by saturating key feed components before the feed components are stripped into their incompatible aromatic cores. The efficacy of this disruptive catalyst system is particularly evident in a hydrocracker configuration that runs in two-stage-recycle operation. The catalyst is a self-supported multi-metallic catalyst prepared from a precursor in the hydroxide form, and the catalyst must be toward the top level of the second stage of the two-stage system.

The invention relates to the use of ruthenium complexes, which are homogeneous catalysts and/or precatalysts of the olefin metathesis reaction, which lead to the production of alkenes containing an internal (non-terminal) double C═C bond. ##STR00001##