Patent classifications
B01J31/2243
Catalyst for ring expansion metathesis polymerization of cyclic monomers
A tetraanionic OCO pincer ligand metal-oxo-alkylidene complex is prepared from a trianionic pincer ligand supported metal-alkylidyne. The metal can be tungsten or other group 5-7 transition metal. The tetraanionic pincer ligand metal-oxo-alkylidene complex, a trianionic OCO pincer ligand metal complex, or a trianionic ONO pincer ligand metal complex can be used to polymerize cycloalkenes. The poly(cycloalkene)s are predominantly cis-alkene macrocyclics.
Hydrogenation catalyst compositions and their use for hydrogenation of nitrile rubber
This invention relates to novel hydrogenation catalyst compositions obtainable from reacting metal-based complex hydrogenation catalysts with specific co-catalysts and to a process for selectively hydrogenating nitrile rubbers in the presence of such novel hydrogenation catalyst compositions.
Long shelf life stable photoactive mass polymerizable polycycloolefin compositions as optical materials
Embodiments in accordance with the present invention encompass compositions encompassing a latent organo-ruthenium compound, a photosensitizer and one or more monomers which undergo ring open metathesis polymerization (ROMP) when said composition is exposed to suitable actinic radiation to form a substantially transparent film or a three dimensional object. Surprisingly, the compositions are very stable at ambient conditions to temperatures up to 80° C. for several weeks and undergo mass polymerization only when subjected to actinic radiation under inert atmosphere such as for example a blanket of nitrogen. Accordingly, compositions of this invention are useful in various opto-electronic applications, including as 3D printing materials, coatings, encapsulants, fillers, leveling agents, among others.
METHODS FOR PREPARING SUBSTITUTED CHROMANONE DERIVATIVES
The present disclosure relates to a method for preparing a compound of formula (I).
##STR00001##
In the compound of formula (I), n may be 0 to 5 and each of R.sub.1, R.sub.2, R.sub.3, and R.sub.4 may be independently selected from the group consisting of H, —O-Alkyl, halo, alkyl, —CN, or —NO.sub.3.
CATALYST FOR RING EXPANSION METATHESIS POLYMERIZATION OF CYCLIC MONOMERS
A tetraanionic OCO pincer ligand metal-oxo-alkylidene complex is prepared from a trianionic pincer ligand supported metal-alkylidyne. The metal can be tungsten or other group 5-7 transition metal. The tetraanionic pincer ligand metal-oxo-alkylidene complex, a trianionic OCO pincer ligand metal complex, or a trianionic ONO pincer ligand metal complex can be used to polymerize cycloalkenes. The poly(cycloalkene)s are predominantly cis-alkene macrocyclics.
HETEROBIMETALLIC CATALYSTS AND SITE-DIFFERENTIATED LIGANDS FOR PREPARATION THEREOF
Phosphine phosphonate and phenoxyphosphine ligands bearing polyethylene glycol (PEG) chains are used as described herein to produce heterobimetallic catalysts. The ligands can be metallated selectively with palladium or nickel and secondary metal ions to provide well-defined heterobimetallic compounds. These heterobimetallic complexes exhibit accelerated reaction rates and greater thermal stability in olefin polymerization compared to other catalysts.
Chiral binuclear metal complexes for stereoselective hydrolysis of saccharides and glycosides
Disclosed herein is a class of chiral binuclear metal complexes for stereoselective hydrolysis of saccharides and glycosides, and more particular chiral binuclear transition metal complex catalysts that discriminate epimeric glycosides and α- and β-glycosidic bonds of saccharides in aqueous solutions at near physiological pHs. The chiral binuclear metal complexes include a Schiff-base-type ligand derived from a chiral diamino building block, and a binuclear transition metal core, each which can be varied for selectivity. The metal core is a Lewis-acidic metal ion, such as copper, zinc, lanthanum, iron and nickel. The Schiff-base may be a reduced or non-reduced Schiff-base derived from aliphatic linear, aliphatic cyclic diamino alcohols or aromatic aldehydes. The ligand can be a penta- or heptadentate ligand derived from pyridinecarbaldehydes, benzaldehydes, linear or cyclic diamines or diamino alcohols.
HETEROGENEOUS CATALYSTS, AND USES THEREOF
Provided herein are heterogeneous catalysts suitable for use in carbonylation reactions, including the production of acrylic acid from ethylene oxide and carbon monoxide on an industrial scale. The production may involve various unit operations, including, for example: a beta-propiolactone production system configured to produce beta-propiolactone from ethylene oxide and carbon monoxide; a polypropiolactone production system configured to produce polypropiolactone from beta-propiolactone; and an acrylic acid production system configured to produce acrylic acid with a high purity by thermolysis of polypropiolactone.
Method for converting hydroxyl group of alcohol
The present invention relates to: a method for converting a hydroxyl group of an alcohol; and a catalyst which makes the method possible. A method for converting a hydroxyl group of an alcohol according to the present invention is characterized by producing a compound represented by CH(R.sup.1)(R.sup.2)Nu (wherein R.sup.1, R.sup.2 and Nu are as defined below) by reacting an alcohol represented by CH(R.sup.1)(R.sup.2)OH (wherein each of R.sup.1 and R.sup.2 represents a hydrogen atom, an optionally substituted alkyl group, or the like) and a compound having an active proton, which is represented by H-Nu (wherein Nu represents a group represented by —CHX.sup.1-EWG.sup.1 or —NR.sup.3R.sup.4; X.sup.1 represents a hydrogen atom or the like; EWG.sup.1 represents an electron-withdrawing group; and each of R.sup.3 and R.sup.4 represents a hydrogen atom, an optionally substituted alkyl group, or the like), with each other in the presence of a complex of a group 7-11 metal of the periodic table and at least one solid base that is selected from the group consisting of layered double hydroxides, composite oxides and calcium hydroxide.
Method for oxidative cleavage of compounds with unsaturated double bond
A method for oxidative cleavage of a compound with an unsaturated double bond is provided. The method includes the steps of: (A) providing a compound (I) with an unsaturated double bond, a trifluoromethyl-containing reagent, and a catalyst; ##STR00001## wherein, the catalyst is represented by Formula (II):
M(O).sub.mL.sup.1.sub.yL.sup.2.sub.z (II); wherein, M, L.sup.1, L.sup.2, m, y, z, R.sub.1, R.sub.2 and R.sub.3 are defined in the specification; and (B) mixing the compound with an unsaturated double bond and the trifluoromethyl-containing reagent to perform an oxidative cleavage of the compound with the unsaturated double bond by using the catalyst in air or under oxygen atmosphere condition to obtain a compound represented by Formula (III): ##STR00002##