摘要:
This disclosure relates generally to olefin metathesis, and more particularly relates to the synthesis of terminal alkenes from internal alkenes using a cross-metathesis reaction catalyzed by an olefin metathesis catalyst. According to one aspect, for example, a method is provided for synthesizing a terminal olefin, the method comprising contacting, in the presence of a ruthenium alkylidene metathesis catalyst, an olefinic substrate comprised of at least one internal olefin with a cross metathesis partner comprised of an alpha olefinic reactant, under reaction conditions effective to allow cross-metathesis to occur, wherein the reaction conditions include a reaction temperature of at least 35 °C. The methods, compositions, reactions and reaction systems herein disclosed have utility in the fields of catalysis, organic synthesis, and industrial chemistry.
摘要:
The present invention relates to a low molecular weight optionally hydrogenated nitrile rubber and a process for preparing a low molecular weight optionally hydrogenated nitrile rubber by molecular weight degradation of nitrile rubbers via a metathesis process in the presence of a transition metal complex catalyst in a specific reaction mixture, a polymer composite comprising at least one optionally hydrogenated nitrile rubber, at least one cross-linking agent and/or curing system, optionally at least one filler and optionally further auxiliary products for rubbers and a shaped article comprising the optionally hydrogenated nitrile rubber or the composite.
摘要:
Изобретение относится к органическому синтезу и касается области производства гомогенного катализатора для получения эфиров акриловой кислоты по реакции метатезиса малеатов с этиленом. Разработаны два варианта катализатора для получения эфиров акриловой кислоты по реакции метатезиса диалкилмалеатов с этиленом: катализатор формулы: (I) и катализатор формулы: (II) Использование данных катализаторов позволяет повысить число их оборотов в реакции метатезиса диалкилмалеатов с этиленом как в условиях умеренных температур (около 50°C) при проведении процесса без отгонки продукта, так и при температурах около 120°C, когда образующийся акрилат отгоняют из реакци- онной смеси. Разработана также каталитическая композиция, позволяющая повысить не только число оборотов, но и время жизни катализатора, наиболее эффективная при температурах около 120°C, когда образующийся акрилат отгоняют из реакционной смеси. Такая композиция содержит указанный катализатор и 2-изoпpoпoкcиcтиpoлa или его производное при соотношении: 1 мольный эквивалент катализатора на 5 - 100 мольных эквивалентов 2-изoпpoпoкcиcтиpoлa или его производного.
摘要:
A method of converting at least one first alkane to a mixture of at least one low molecular weight alkane (optionally also including additional lower and/or higher molecular weight alkanes) and at least one high molecular weight alkane, comprising: reacting a first alkane in the presence of dual catalyst system comprising a first catalyst (i.e., a hydrogen transfer catalyst and preferably an iridium pincer complex catalyst) and a second catalyst (i.e., a metathesis catalyst) to produce a mixture of low and high molecular weight alkanes.
摘要:
Catalysts are described comprising the reaction product of a metal compound and a compound containing a phosphirene moiety of general formula (I) in which R 1 , R 2 and R 3 represent independently hydrogen, alkyl (having between 1 and 24 carbon atoms), substituted alkyl or cycloalkyl, heterocycle or substituted heterocycle, aryl or substituted aryl, ferrocenyl or ruthenocyl. Catalysts based on e.g. palladium and such phosphirene compounds may be used for example in hydrogenation, Heck or amination reactions.
摘要:
Catalytic complexes including a metal atom having anionic ligands, at least one nucleophilic carbene ligand, and an alkylidene, vinylidene, or allenylidene ligand. The complexes are highly stable to air, moisture and thermal degradation. The complexes are designed to efficiently carry out a variety of olefin metathesis reactions.
摘要:
The invention relates to a complex compound of ruthenium of general structural formula (I), wherein X and X are the same or different and represent an anionic ligand, R and R are the same or different independently of each other but can also have a cycle and R and R represent hydrogen and/or a hydrocarbon group wherein the ligand L is an N-heterocyclic carbene and wherein the ligand L is a neutral electron donor, especially an N-heterocyclic carbene or an amine, imine, phosphane, phosphite, stibine, arsine, a carbonyl compound, a carboxyl compound, nitrile, alcohol, ether, thiol or thioether, R , R , R and R representing hydrogen and/or hydrocarbon groups. The invention also relates to a method for producing acyclic olefins with two or more carbon atoms and/or cyclic olefins with four or more carbon atoms from acyclic olefins with two or more carbon atoms and/or from cyclic olefins with four or more carbon atoms by means of an olefin-metathesis reaction in the presence of at least one catalyst, a complex compound being used as the catalyst and R' , R' , R' and R' representing hydrogen and/or hydrocarbon groups.
摘要:
Olefin metathesis between an acrylate monomer and a polyene comprising molecule or polymer is employed as a method of cross-metathesizing or depolymerizing the molecule. The metathesis reaction forms a telechelic acrylate molecule that is a monomer, oligomer or polymer. The telechelic acrylate molecule can be employed as a monomer for condensation polymerization.
摘要:
A method for suppressing isomerization of an olefin metathesis product produced in a metathesis reaction includes adding an isomerization suppression agent to a mixture that includes the olefin metathesis product and residual metathesis catalyst from the metathesis reaction under conditions that are sufficient to passivate at least a portion of the residual metathesis catalyst. The isomerization suppression agent includes (i) a salt and/or an ester of a phosphorous oxo acid, and/or (ii) a derivative of the phosphorous oxo acid in which at least one P-H bond has been replaced by a P-C bond, and/or (iii) a salt and/or an ester of the derivative. Methods of refining natural oils and methods of producing fuel compositions are described.
摘要:
A self-metathesis process for the production of unsaturated dicarboxylic fatty diacids and/or unsaturated dicarboxylic fatty diesters, wherein unsaturated carboxylic fatty acids and/or esters of unsaturated carboxylic fatty acids are reacted in the presence of at least one defined ruthenium based catalyst compound. A catalyst enhancer compound selected from a sacrificial catalyst or a non-catalyst enhancer may also be used. The process exhibits improved reaction times and/or the catalyst can be used at very low concentrations.