52 results about "Dehydrogenative coupling of silanes" patented technology

Compounds and method of preparation of Si—X and Ge—X compounds (X═N, P, As and Sb) via dehydrogenative coupling between the corresponding unsubstituted silanes and amines (including ammonia) or phosphines catalyzed by metallic catalysts is described. This new approach is based on the catalytic dehydrogenative coupling of a Si—H and a X—H moiety to form a Si—X containing compound and hydrogen gas (X═N, P, As and Sb). The process can be catalyzed by transition metal heterogenous catalysts such as Ru(0) on carbon, Pd(0) on MgO) as well as transition metal organometallic complexes that act as homogeneous catalysts. The —Si—X products produced by dehydrogenative coupling are inherently halogen free. Said compounds can be useful for the deposition of thin films by chemical vapor deposition or atomic layer deposition of Si-containing films.

Methods are disclosed of making linear and cross-linked, HMW (high molecular weight) polysilanes and polygermanes, polyperhydrosilanes and polyperhydrogermanes, functional liquids containing the same, and methods of using the liquids in a range of desirable applications. The silane and germane polymers are generally composed of chains of Si and/or Ge substituted with R′ substituents, where each instance of R′ is, for example, independently hydrogen, halogen, alkenyl, alkynyl, hydrocarbyl, aromatic hydrocarbyl, heterocyclic aromatic hydrocarbyl, SiR″₃, GeR″₃, PR″₂, OR″, NR″₂, or SR″; where each instance of R″ is independently hydrogen or hydrocarbyl. The cross-linked polymers can be synthesized by dehalogenative coupling or dehydrocoupling. The linear polymers can be synthesized by ring-opening polymerization. The polymers can be further modified by halogenation and/or reaction with the source of hydride to furnish perhydrosilane and perhydrogermane polymers, which are used in liquid ink formulations. The synthesis allows for tuning of the liquid properties (e.g., viscosity, volatility, and surface tension). The liquids can be used for deposition of films and bodies by spincoating, inkjetting, dropcasting, etc., with or without the use of UV irradiation. The deposited films can be converted into amorphous and polycrystalline silicon or germanium, and silicon or germanium oxide or nitride by curing at 400-600 DEG C. and (optionally) laser- or heat-induced crystallization (and/or dopant activation, when dopant is present).

The present invention discloses 2,2'-bipyridine, a catalytic coupling synthesis method and applications thereof. According to the method, Raney nickel is adopted as a catalyst and a reaction aid is added to an autoclave to catalyze pyridine to be subjected to dehydrogenation so as to directly couple to synthesize 2,2'-bipyridine, wherein the chemical formula of the reaction aid is represented by R-X, R represents alkyl or alkoxy or amino, and X represents an alkali metal or third main group element. According to the present invention, the pyridine is adopted as the raw material and the dehydrogenation coupling is performed to obtain the 2,2'-bipyridine, such that the raw material is easy to obtain, the pyridine chlorination process is eliminated, the process is simple, the production cost is substantially reduced, the use of halogenated pyridine is avoided, the production pollution is reduced, and the environmental protection is provided; the used catalyst has the cheap price and effectively replaces the expensive precious metal so as to reduce the catalyst cost; and the reaction aid is added during the reaction process so as to effectively improve the pyridine raw material conversion rate and improve the 2,2'-bipyridine yield, and the method is suitable for factory scale production.

The invention relates to a method for preparing ethylene glycol by photocatalytic methanol dehydrogenation coupling, belonging to the chemical field, which comprises the following steps: adding additive and photocatalyst into a solvent, uniformly dispersing, removing oxygen in the system, and then carrying out photocatalytic reaction to prepare ethylene glycol, wherein the solvent is methanol or methanol-water system, wherein the additive comprises at least one of an aromatic organic substance, a fluorine-containing organic compound and a fluorinated salt, and the photocatalyst is a semiconductor catalyst or a modified semiconductor catalyst. Using a small amount of additives can significantly promote methanol photocatalytisis to prepare ethylene glycol. The reaction is carried out in an inert atmosphere and has the characteristics of high catalytic activity, high product selectivity, mild reaction conditions and the like.

The invention discloses a hierarchical pore molecular sieve packaged platinum-nickel bimetallic nano catalytic material and a preparation method and application thereof. The catalytic material is prepared from a modified silicon source, an aluminum source, a quaternary ammonium salt structure-directing agent and a PtNi bimetallic precursor through a hydrothermal synthesis method, and the modified silicon source is prepared by modifying nano silicon dioxide through a silane coupling agent. The PtNi bimetallic precursor is prepared by electrostatic self-assembly of an amine structure directing agent, Pt and Ni sources, and based on the total mass of the catalytic material, the mass percent of nickel is 0.1-20wt%, and the mass percent of platinum is 0.1-5wt%. A one-step method is adopted, a PtNi bimetallic precursor is introduced in situ in the process of synthesizing the hierarchical pore molecular sieve, and selective packaging of the PtNi bimetallic nanocluster in a hierarchical pore molecular sieve side cage is achieved. The catalytic material is applied to a reaction for catalyzing dehydrogenation coupling of pyridine to synthesize 2,2'-dipyridyl, has the advantages of low dosage, few side reactions, short process and the like, and has a good application prospect in the fields of adsorption separation, petrochemical engineering, fine chemical production and the like.

The present invention relates to novel manganese complexes and their use, inter alia, for homogeneous catalysis in (1) the preparation of imine by dehydrogenative coupling of an alcohol and amine; (2) C—C coupling in Michael addition reaction using nitriles as Michael donors; (3) dehydrogenative coupling of alcohols to give esters and hydrogen gas (4) hydrogenation of esters to form alcohols (including hydrogenation of cyclic esters (lactones) or cyclic di-esters (di-lactones), or polyesters); (5) hydrogenation of amides (including cyclic dipeptides, lactams, diamide, polypeptides and polyamides) to alcohols and amines (or diamine); (6) hydrogenation of organic carbonates (including polycarbonates) to alcohols or hydrogenation of carbamates (including polycarbamates) or urea derivatives to alcohols and amines; (7) dehydrogenation of secondary alcohols to ketones; (8) amidation of esters (i.e., synthesis of amides from esters and amines); (9) acylation of alcohols using esters; (10) coupling of alcohols with water and a base to form carboxylic acids; and (11) preparation of amino acids or their salts by coupling of amino alcohols with water and a hydrogenative coupling of alcohols and amines; (13) preparation of imides from diols.

The invention discloses a method for preparing methyl heptanone. According to the method, 3-methyl-2-butene-1-ol and acetone undergoes a selective dehydrogenation coupling reaction under the action ofa rhodium catalyst, alkali and an optional assistant to generate methyl heptenone. Compared with the prior art, the method has the advantages that cheap and easily available 3-methyl-2-butene-1-ol and acetone are used as raw materials; the methyl heptenone with high additional value is prepared through a one-step reaction; and the method is high in atom utilization rate, low in generation of three wastes, mild in conditions and high in selectivity and yield.

The invention discloses a novel preparation method of 4, 4'-dinitrobibenzyl. According to the method, p-nitrotoluene is used as a reactant, oxygen is used as an oxidizing agent, ethanol is used as a solvent, transition metal doped FDU-12 mesoporous molecular sieve supported guanidine salt ionic liquid is used as a catalyst, and 4, 4 '-dinitrobibenzyl is prepared through high-selectivity oxidative dehydrogenation coupling reaction. After the reaction is finished, the catalyst phase and the product phase are easily subjected to heterogeneous separation and can be well recycled. The method has the advantages of simple operation, mild reaction conditions, small catalyst dosage, high reaction efficiency and selectivity, and small discharge of three wastes, and is a novel green and clean preparation method.

The present invention relates to a drainage aid composition and its use in pulp washing process. More particulary, this invention relates to drainage aid composition of silicone polyethers prepared via zinc catalized dehydrogenative coupling of alcohol terminated polyethers with silicone oligomers and polymers comprising of at least one silicon bonded hydrogen. The compostion of this invention exhibit excellent drainage properties.

The invention discloses a polysilyl ether and a method for synthesizing the polysilyl ether, and a series of polysilyl ethers with novel structures are obtained by catalyzing selective dehydrogenation coupling of prochiral silane and diol by taking a diphosphine ligand complex of cheap metal cobalt as a catalyst. The molar ratio of the cobalt complex to the monomer containing the hydroxyl silane is (0.005-0.020): 1. The reaction activity is high, and the maximum number-average molecular weight of the polysilyl ether can reach 3.23 * 10 < 4 >. The catalyst is convenient to prepare, simple and practical in reaction operation and mild in reaction condition; the synthesized polysilyl ether is derived from different types of monomers. In addition, the catalyst can be used for synthesizing polysilyl ether by a hydrosilylation/dehydrogenation coupling two-step one-pot method. When the chiral diphosphine ligand is used, chiral polysilyl ether can be obtained through the reaction. The synthesized chiral polysilyl ether has potential practical application value in the field of chiral separation.

The invention provides a kaolin-loaded nano-iron catalyst and the application thereof in catalyzing cross dehydrogenation coupling reaction, and belongs to the technical field of catalysts. Accordingto the kaolin-loaded nano-iron catalyst provided in the invention, the kaolin-loaded nano-iron catalyst comprises a kaolin carrier and nano-iron loaded in the kaolin carrier. When the kaolin-loaded nano-iron catalyst provided by the invention is used for catalyzing cross dehydrogenation coupling reaction of cyclic ether C(sp3) H bonds and aromatic formic acid, activation and direct esterificationof the cyclic ether C(sp3) H bonds can be catalyzed, and a good catalytic effect is achieved. Meanwhile, the kaolin-loaded nano-iron catalyst provided by the invention is a heterogeneous catalyst, hasthe advantages of low cost, no toxicity and environmental sustainability, can be recycled for multiple times, and is very beneficial to application in modern industrial production.

A process for making methyl esters in high yields. The process comprises contacting aliphatic or aromatic aldehydes and methanol with a homogeneous dimeric ruthenium catalyst, to catalyze the dehydrogenative coupling between aliphatic or aromatic aldehydes and methanol. The reaction is highly selective (<99.9%) toward the formation of methyl esters over homoesters and alcohols and operates at temperatures of less than 100° C. for 2-8 hours.