A method of forming TiO.sub.2ZnO nanoparticles coated by a copper (II) complex includes forming a mononuclear copper complex by treating a ligand with Cu.sup.2+ ions; and immobilizing the mononuclear copper complex on TiO.sub.2ZnO nanoparticles to obtain the TiO.sub.2ZnO nanoparticle coated by the copper (II) complex. The TiO.sub.2ZnO nanoparticles coated by a copper (II) complex thus produced have improved catalytic effectiveness and increased efficiency by reducing catalytic reaction time and temperature, particularly in methods of catalyzing oxidation of an alcohol or of catalyzing decarboxylative bromination of an acid.

Methods for the production of 2,4-dihydroxybutyrate (2,4-DHB) from erythrose and other four-carbon sugars are disclosed. The improved methods facilitate the production of 2,4-DHB that is a precursor for biorenewable and animal nutrition chemicals among others.

Methods for the production of 2,4-dihydroxybutyrate (2,4-DHB) from erythrose and other four-carbon sugars are disclosed. The improved methods facilitate the production of 2,4-DHB that is a precursor for biorenewable and animal nutrition chemicals among others.

Methods for the production of 2,4-dihydroxybutyrate (2,4-DHB) from erythrose and other four-carbon sugars are disclosed. The improved methods facilitate the production of 2,4-DHB that is a precursor for biorenewable and animal nutrition chemicals among others.

A method of forming TiO.sub.2ZnO nanoparticles coated by a copper (II) complex includes forming a mononuclear copper complex by treating a ligand with Cu.sup.2+ ions; and immobilizing the mononuclear copper complex on TiO.sub.2ZnO nanoparticles to obtain the TiO.sub.2ZnO nanoparticle coated by the copper (II) complex. The TiO.sub.2ZnO nanoparticles coated by a copper (II) complex thus produced have improved catalytic effectiveness and increased efficiency by reducing catalytic reaction time and temperature, particularly in methods of catalyzing oxidation of an alcohol or of catalyzing decarboxylative bromination of an acid.

A method of forming TiO.sub.2ZnO nanoparticles coated by a copper (II) complex includes forming a mononuclear copper complex by treating a ligand with Cu.sup.2+ ions; and immobilizing the mononuclear copper complex on TiO.sub.2ZnO nanoparticles to obtain the TiO.sub.2ZnO nanoparticle coated by the copper (II) complex. The TiO.sub.2ZnO nanoparticles coated by a copper (II) complex thus produced have improved catalytic effectiveness and increased efficiency by reducing catalytic reaction time and temperature, particularly in methods of catalyzing oxidation of an alcohol or of catalyzing decarboxylative bromination of an acid.

Disclosed is a practical method for production of 3,3-difluoro-2-hydroxypropionic acid, which is important as pharmaceutical and agrichemical intermediates. The method includes forming a 4,4-difluoro-2,2-dichloro-3-oxobutanoic acid ester by reaction of a 4,4-difluoro-3-oxobutanoic acid ester with chlorine (Cl.sub.2), forming 3,3-difluoro-1,1-dichloro-2-propanone by reaction of the chlorination product with an acid, and then, reacting the degradation product with a basic aqueous solution.

Disclosed is a practical method for production of 3,3-difluoro-2-hydroxypropionic acid, which is important as pharmaceutical and agrichemical intermediates. The method includes forming a 4,4-difluoro-2,2-dichloro-3-oxobutanoic acid ester by reaction of a 4,4-difluoro-3-oxobutanoic acid ester with chlorine (Cl.sub.2), forming 3,3-difluoro-1,1-dichloro-2-propanone by reaction of the chlorination product with an acid, and then, reacting the degradation product with a basic aqueous solution.

Disclosed is a practical method for production of 3,3-difluoro-2-hydroxypropionic acid, which is important as pharmaceutical and agrichemical intermediates. The method includes forming a 4,4-difluoro-2,2-dichloro-3-oxobutanoic acid ester by reaction of a 4,4-difluoro-3-oxobutanoic acid ester with chlorine (Cl.sub.2), forming 3,3-difluoro-1,1-dichloro-2-propanone by reaction of the chlorination product with an acid, and then, reacting the degradation product with a basic aqueous solution.

A catalyst system includes a complex having formula I which advantageously has a sterically protecting N-heterocyclic carbene (NHC) carbene-pyridine ligand to handle harsh reactions conditions than many prior art catalysts: ##STR00001##
wherein M is a transition metal; o is 0, 1, 2, 3, or 4; R.sub.1 is a C.sub.1-6 alkyl, a C.sub.6-18 aryl, or an optionally substituted C.sub.5-18 heteroaryl. In a refinement, R.sub.1 is methyl, ethyl, butyl, n-propyl, isopropyl, n-butyl, sec-butyl, or t-butyl; R.sub.2, R.sub.3, R.sub.3 are independently an optionally substituted C.sub.1-6 alkyl, halo (e.g., Cl, F, Br, etc), NO.sub.2, an optionally substituted C.sub.6-18 aryl, or an optionally substituted C.sub.5-18 heteroaryl; R.sub.4, R.sub.4 are independently an optionally substituted C.sub.1-6 alkyl, halo, NO.sub.2, an optionally substituted C.sub.6-18 aryl, or an optionally substituted C.sub.5-18 heteroaryl; and X.sup. is a negatively charge counter ion and L.sub.1, L.sub.2 are each independently a neutral ligand.