Abstract: The present invention provides a metal-oxo complex represented by the following general formula (1), wherein in the general formula (1) above, “M” represents a molybdenum atom or a tungsten atom; “A” represents a carbon atom, a silicon atom, a germanium atom, a tin atom or a lead atom; X1 and X2 each independently represent a halogen atom; R1 to R5 each independently represent a hydrogen atom, a straight or branched chain alkyl group that is substituted or unsubstituted and has 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms; each of R1 to R3 may be bonded to one another to form a ring.

Abstract: The present invention provides a metal-oxo complex represented by the following general formula (1), wherein in the general formula (1) above, “M” represents a molybdenum atom or a tungsten atom; “A” represents a carbon atom, a silicon atom, a germanium atom, a tin atom or a lead atom; X1 and X2 each independently represent a halogen atom; R1 to R5 each independently represent a hydrogen atom, a straight or branched chain alkyl group that is substituted or unsubstituted and has 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms; each of R1 to R3 may be bonded to one another to form a ring.

Abstract: Provided is a catalyst for producing hydrogen, which catalyst has higher performance than conventional catalysts since, for example, it exhibits a certain high level of activity in an aqueous formic acid solution at high concentration even without addition of a solvent, amine and/or the like. The metal phosphine complex is a metal phosphine complex represented by General Formula (1): MHm(CO)Ln, wherein M represents an iridium, iron, rhodium or ruthenium atom; in cases where M is an iridium or rhodium atom, m=3 and n=2, and in cases where M is an iron or ruthenium atom, m=2 and n=3; and the number n of Ls each independently represent a tri-substituted phosphine represented by General Formula (2): PR1R2R3. The catalyst for producing hydrogen comprises the metal phosphine complex as a constituent component.

Abstract: A catalyst contains a metal complex compound represented by the following general formula (I). In the formula (I), M is a metal ion such as ruthenium, L1 is a cyclic or acyclic, neutral or minus 1-valent unsaturated hydrocarbon group of 1 to 30 carbon atoms which may have a substituent, L2 and L3 are each independently chlorine or the like, and L4 is a compound bonded to M through phosphorus or arsenic and represented by the following general formula (IIa) or (IIb). In the formulas (IIa) and (IIb), E is phosphorus or arsenic, Y1 is oxygen or sulfur, Y2, Y3 and Y4 are each independently a hydrogen atom, an aryl group or the like, and H is a hydrogen atom.

Abstract: Provided is a catalyst for producing hydrogen, which catalyst has higher performance than conventional catalysts since, for example, it exhibits a certain high level of activity in an aqueous formic acid solution at high concentration even without addition of a solvent, amine and/or the like. The metal phosphine complex is a metal phosphine complex represented by General Formula (1): MHm(CO)Ln, wherein M represents an iridium, iron, rhodium or ruthenium atom; in cases where M is an iridium or rhodium atom, m=3 and n=2, and in cases where M is an iron or ruthenium atom, m=2 and n=3; and the number n of Ls each independently represent a tri-substituted phosphine represented by General Formula (2): PR1R2R3. The catalyst for producing hydrogen comprises the metal phosphine complex as a constituent component.

Abstract: A catalyst contains a metal complex compound represented by the following general formula (I). In the formula (I), M is a metal ion such as ruthenium, L1 is a cyclic or acyclic, neutral or minus 1-valent unsaturated hydrocarbon group of 1 to 30 carbon atoms which may have a substituent, L2 and L3 are each independently chlorine or the like, and L4 is a compound bonded to M through phosphorus or arsenic and represented by the following general formula (IIa) or (IIb). In the formulas (IIa) and (IIb), E is phosphorus or arsenic, Y1 is oxygen or sulfur, Y2, Y3 and Y4 are each independently a hydrogen atom, an aryl group or the like, and H is a hydrogen atom.

Abstract: The disclosure described a process for producing an .alpha.-olefin oligomer, which comprises carrying out oligomerization of an .alpha.-olefin in a solvent in the presence of a catalytically effective amount of a chromium-based catalyst system composed of a combination of at least (a) a chromium compound, (b) a nitrogen-containing compound of at least one selected from the group consisting of an amine, an amide and an imide, (c) an alkylaluminum compound and (d) a halogen-containing compound,wherein each of the .alpha.-olefin, the chromium compound (a), the nitrogen-containing compound (b) of at least one selected from the group consisting of an amine, an amide and an imide, the alkylaluminum compound (c) and the halogen-containing compound (d) is supplied to a reaction system in a mode that the chromium compound (a) and the alkylaluminum compound (c) do not contact each other before each of said compounds (a) to (d) and the .alpha.-olefin coexists in the reaction solvent and the oligomerization of an .alpha.

Abstract: The disclosure describes a process for preparing .alpha.-olefin oligomers, which comprises carrying out oligomerization of an .alpha.-olefin in a solvent by reacting said .alpha.-olefin in a chromium-based catalyst system composed of a combination of at least a chromium compound, an amine or metal amide, and an alkylaluminum compound, in a contacting mode that the chromium compound and the alkylaluminum compound are not previously contacted with each other.

Abstract: A method for oligomerizing an .alpha.-olefin in the presence of a catalyst comprising a specific chromium compound including chromium atom and pyrrolyl group and an alkylaluminum compound, wherein the .alpha.-olefin is contacted to the chromium compound and the alkylaluminum compound without preliminarily contacting the chromium compound to either the .alpha.-olefin or the alkylaluminum compound.

Abstract: A method for oligomerizing an .alpha.-olefin in the presence of a catalyst comprising a specific chromium compound including chromium atom and pyrrolyl group and an alkylaluminum compound, wherein the .alpha.-olefin is contacted to the chromium compound and the alkylaluminum compound without preliminarily contacting the chromium compound to either the .alpha.-olefin or the alkylaluminum compound.