The present invention relates to a transition metal-based heterogeneous carbonylation reaction catalyst that has an excellent catalytic activity and selectivity in the carbonylation reaction and is easily separated from a product, by crosslinking polymerizing a transition metal-based homogeneous catalyst unit through a Friedel-Craft reaction; and a method for preparing lactone using the same. The transition metal-based heterogeneous carbonylation reaction catalyst allows to produce lactone or succinic anhydride with an epoxide compound while showing a high selectivity, and can be applied in industrial very usefully due to easy separation from the product and thus reusing thereof.

A composition of a photocatalyst, a method of manufacturing the photocatalyst, and a method of chemically reducing carbon dioxide to carbon monoxide using the photocatalyst under visible-light irradiation is provided. The photocatalyst comprises a transition metal ion and graphitic carbon nitride and includes single metal sites on carbon nitride. Under visible light, the metal sites that are coordinated to nitrogen atoms get activated, without the use of additional ligands, to catalyze the reduction of carbon dioxide to selectively produce carbon monoxide. The photocatalytic reduction of carbon dioxide to carbon monoxide is highly efficient, resulting a turnover number of more than 800 for carbon monoxide production in 2 hours. The composition is useful in converting carbon dioxide into useful chemicals and carbon-based fuels. A functional model of molecular catalysts for efficient carbon dioxide reduction is also present.

The present invention relates to an organic zinc catalyst which exhibits more improved catalytic activity than conventional organic zinc catalysts during a polymerization process for the preparation of a polyalkylene carbonate resin and is capable of preventing an aggregation phenomenon during a reaction, a method for preparing the same, and a method for preparing a polyalkylene carbonate resin using the organic zinc catalyst. The method for preparing an organic zinc catalyst includes the step of reacting a zinc precursor with a dicarboxylic acid in the presence of a polyether derivative to form a zinc dicarboxylate-based catalyst.

The present invention relates to the field of organic synthesis. More specifically, it concerns a process for the selective reduction of a C.sub.3-C.sub.70 substrate containing one or more carbonyl or carboxylic functional groups into the corresponding 5 alcohol diol, or polyalcohol in the presence of a silane and at least one catalyst or pre-catalyst in the form of a zinc complex. The Zinc complex of formula (I) or (II) is also part of the invention.

The present invention relates to the field of polymerisation catalysts, and systems comprising these catalysts for polymerising carbon dioxide and an epoxide, a lactide and/or lactone, and/or an epoxide and an anhydride. The catalyst is of formula (I): ##STR00001##
wherein at least one of M.sub.1 or M.sub.2 is selected from Ni(II) and Ni(III)-X. A process for the reaction of carbon dioxide with an epoxide; an epoxide and an anhydride; and/or a lactide and/or a lactone in the presence of the catalyst is also described.

Metal-organic frameworks (MOFs) may have Zn(II), Pb(II), and/or Cd(II) as a central metal ion; a 4,4-bipyridylethylene (bpe) ligand as a first ligand; and fumaric acid (fum) and/or oxalic acid (ox) as a second ligand, wherein the 4,4-bipyridylethylene ligands are stacked in the MOF, and wherein a distance between two consecutive 4,4-bipyridylethylene ligands is less than 5 . Cycloadditions, particularly photoinduced [2+2] cycloadditions may be catalyzed by such MOFs, and/or the conversion of photoinduced [2+2] cycloadditions in inventive MOFs may be increased by mechanical force, such as by grinding.

The invention describes single-site metal catalysts such as Pt single-site centers with a 3,6-di-2-pyridyl-1,2,4,5-tetrazine (DPTZ) ligand on support such as a powdered MgO, Al.sub.2O.sub.3, CeO.sub.2 or mixtures thereof.

Embodiments of the present disclosure describe a catalyst and/or a precatalyst, in particular a single site catalyst and/or a single site precatalyst, for the oxidation and/or ammoxidation of olefins to produce aldehydes and/or nitriles, methods of preparing a corresponding catalyst and/or precatalyst, in particular single site catalyst and/or single site precatalyst, and methods of using said catalyst and/or precatalyst, in particular said single site catalyst and/or single site precatalyst, to produce aldehydes and/or nitriles.

Metal ion-directed carboxylic acid functionalized polyoxometalate hybrid compounds, and their preparation method and applications in catalyzing the degradation of chemical warfare agent simulants. In the synthesis, Na.sub.2MoO.sub.4, p-hydroxybenzonic acid (PHBA), alanine (Ala), KCl, transition metal cations and As.sub.2O.sub.3 as raw materials and water are used as solvent. At room temperature, 2-chloroethyl ethyl sulfide (CEES) and the prepared polyoxometalate hybrid compounds were mixed together in anhydrous ethanol and stirred, and H.sub.2O.sub.2 was subsequently added into the reaction system. The catalytic reaction for the degradation of CEES was finished within 5 min under stirring. In the catalytic hydrolysis of diethyl cyanophosphonate (DECP), the catalyst, DECP, DMF and H.sub.2O were put together and mixed fully. The prepared polyoxometalate hybrid compounds have the advantages of high conversion, high selectivity and easy recyclability in catalyzing the degradation of two types of chemical warfare agent simulant.

The present invention discloses a process for the photocatalytic splitting of water using self-assembled metalloporphyrin 2D-sheet of formula (I) to form hydrogen and oxygen.