The present invention provides a catalyst system for producing cyclic carbonates comprising: a pre-catalyst, which is BiCl.sub.3 having amounts in the range from 5 to 10% by weight of silica support; a compound having formula (I)

##STR00001## wherein: Y is selected from bromide (Br.sup.−) or iodide (I.sup.−); R.sup.1, R.sup.2, and R.sup.3 are methyl group or R.sup.1, R.sup.2, and R.sup.3 are taken together to form a heteroaryl ring having formula (II)

##STR00002##

and a silica (SiO.sub.2) support.

A layered double hydroxide of the present disclosure includes two or more transition metals and a chelating agent. The layered double hydroxide has an average particle diameter of 10 nm or less.

Disclosed in the present invention are a preparation method for an olefin epoxidation catalyst and applications thereof. The method comprises: loading an auxiliary metal salt onto a silica gel carrier, and carrying out a drying treatment to the silica gel carrier; loading a titanium salt (preferably TiCl.sub.4) onto the silica gel carrier by a chemical vapor deposition method; calcining to obtain a silica gel on which the auxiliary metal oxide and Ti species are loaded; obtaining an catalyst precursor (Ti-MeO—SiO.sub.2 composite oxide) by water vapor washing; loading alkyl silicate (preferably tetraethyl orthosilicate) onto the surface of the catalyst precursor by a chemical vapor deposition method and calcining the catalyst precursor to obtain a Ti-MeO—SiO.sub.2 composite oxide with the surface coated with a SiO.sub.2 layer; and carrying out a silylanization treatment to obtain the catalyst. The catalyst can be applied to a chemical process of propylene epoxidation to prepare propylene oxide, and has an average selectivity to PO up to 96.7%, the method of the present invention and the applications thereof have industrial application prospects.

The present invention refers to a process for a transition metal, particularly nickel-catalyzed cyanation reaction of aryl/vinyl halide using organic nitrile compounds. This new reaction provides a strategically distinct approach to the safe preparation of aryl/vinyl cyanides, which are essential compounds in agrochemistry and medicinal chemistry.

The present invention refers to a process for a transition metal, particularly nickel-catalyzed cyanation reaction of aryl/vinyl halide using organic nitrile compounds. This new reaction provides a strategically distinct approach to the safe preparation of aryl/vinyl cyanides, which are essential compounds in agrochemistry and medicinal chemistry.

A process for synthesis of an organosilicon compound is provided herein. Also, novel organosilicon compounds prepared by the present process is provided herein. The process comprises the reaction of a halosilane with an organofunctional alkyl halide in the presence of a metal catalyst, a promoter, and an optional co-catalyst. The process provides an efficient synthetic route to produce organosilicon compounds. The process also allows synthesis of organosilicon compounds with a plurality of different functional groups.

A process for synthesis of an organosilicon compound is provided herein. Also, novel organosilicon compounds prepared by the present process is provided herein. The process comprises the reaction of a halosilane with an organofunctional alkyl halide in the presence of a metal catalyst, a promoter, and an optional co-catalyst. The process provides an efficient synthetic route to produce organosilicon compounds. The process also allows synthesis of organosilicon compounds with a plurality of different functional groups.

The present invention relates to novel poly(heptazine imides), a photocatalytic system comprising such poly(heptazine imides) and a sulfur source as well as the application thereof in photocatalytic reactions.

The present invention relates to novel poly(heptazine imides), a photocatalytic system comprising such poly(heptazine imides) and a sulfur source as well as the application thereof in photocatalytic reactions.

Disclosed is a nanocatalyst-type nanoscale composition including a nanoparticle semiconductor, plasmonic metal nanoparticles and an organic photosensitiser of the carbo-mer type. Also disclosed is a method for producing such a nano-catalyst. Also disclosed is use of the nanocatalyst for photoelectrolysis, in particular, for the photoelectrolysis of water, as well as to a power source including the nanocatalyst.