- Alkylidene-ruthenium-tin catalysts for the formation of fatty nitriles and esters via cross-metathesis of plant oil derivatives
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The reaction of SnCl2 with the Ru-Cl bond of the Grubbs I catalyst RuCl2(=CHPh)(PCy3)2 (1) gives the complex {[Ru(=CHPh)(SnCl3)(PCy3)]2(μ-Cl) 3}-[HPCy3]+ (2), but containing two diethyl ether solvate molecules. The formal insertion of SnCl2 into one Ru-Cl bond of the Hoveyda II catalyst RuCl2(=CH-C 6H4OPri)(H2IMes) (3) (H 2IMes = N,N′-dimesityl-4,5-dihydroimidazol-2-ylidene) results in formation of the new complex RuCl(SnCl3)(=CH-C6H 4OPri)(H2IMes) (4). The X-ray analyses of 2 and 4 show the presence of very short Ru-Sn bonds (2.5834(9) A mean bond for 2 and 2.5925(12) A for 4) and the retention of short Ru=C bonds (1.895(10) and 1.825(8) A, respectively). Complex 4 shows an excellent catalytic activity for the cross-metathesis of plant oil derivatives, the C11 ω-unsaturated ester and aldehyde and the unsaturated C18 diester with acrylonitrile, and a good activity for their cross-metathesis with methyl acrylate. Good to excellent yield of α,ω-bifunctional compounds, precursors of polyesters and polyamides, were obtained. Complex 2 shows catalytic activity for the self-metathesis of C11 ω-unsaturated aldehyde at low concentration to produce C20 α,ω-dialdehyde.
- Miao, Xiaowei,Blokhin, Anton,Pasynskii, Alexandr,Nefedov, Sergey,Osipov, Sergey N.,Roisnel, Thierry,Bruneau, Christian,Dixneuf, Pierre H.
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- Benzylideneruthenium complexes bearing pyridine-based ligands and their influence on the formation of mono- or bis(pyridine) complexes
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Benzylideneruthenium complexes bearing the N-heterocyclic carbene (NHC) ligand 1,3-bis(2,6-dimethylphenyl)-4,5-dihydroimidazol-2-ylidene (H 2IMe) and one or two pyridine-based ligands have been prepared by treating [RuCl2-(=CHPh) (H
- Zhang, Wen-Zhen,He, Ren,Zhang, Rong
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- Copper-catalyzed direct transformation of simple alkynes to alkenyl nitriles via aerobic oxidative N-incorporation
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A novel direct transformation of aliphatic terminal alkynes to alkenyl nitriles through the incorporation of a nitrogen atom into the simple hydrocarbons has been reported. The usage of inexpensive copper catalyst, O2 as the sole oxidant, broad substrate scope as well as feasibility for "late-stage modification" make this protocol very promising. Mechanistic studies including DFT calculation demonstrate a novel 1,2-hydride shift process for this novel nitrogenation reaction.
- Huang, Xiaoqiang,Li, Xinyao,Jiao, Ning
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- Highly active ruthenium-based catalyst for metathesis of cyano-contained olefins
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Ruthenium benzylidene complex (H2IMes)(2-CH3-C5H4N)(Cl)2Ru{double bond, long}CHPh [H2IMes = 1,3-bis(2,6-dimethylphenyl)-4,5-dihydroimidazol-2-ylidene] (4), which introduced ortho substituted pyridine as dissociating ligand to weaken Ru-N bond and accelerate initiation through steric hindrance, was prepared by the reaction of (H2IMes)(PPh3)(Cl)2Ru{double bond, long}CHPh (1) with 2-methylpyridine and proved to exhibit enhanced catalytic activity for cyano-contained olefin metathesis.
- Zhang, Wenzhen,Zhang, Rong,He, Ren
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- USE OF RUTHENIUM COMPLEXES IN OLEFIN METATHESIS REACTION
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The invention relates to the use of ruthenium complexes, which are homogeneous catalysts and/or precatalysts of the olefin metathesis reaction, which lead to the production of alkenes containing an internal (non-terminal) double C=C bond.
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Page/Page column 19
(2018/05/27)
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- Direct Synthesis of Nitriles from Aldehydes Using an O-Benzoyl Hydroxylamine (BHA) as the Nitrogen Source
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The direct synthesis of nitriles from commercially available or easily prepared aldehydes has been achieved. O-(4-CF3-benzoyl)-hydroxylamine (CF3-BHA) was utilized as the nitrogen source to generate O-acyl oximes in situ with aldehydes, which can be converted to a nitrile with the assistance of a Bronsted acid. Several aliphatic, aromatic, and α,β-unsaturated nitriles that contain different functional groups were prepared in high yields (up to 94% yield). This method has notable advantages, such as simple and mild conditions, high yields, and good functional group tolerance.
- An, Xiao-De,Yu, Shouyun
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supporting information
p. 5064 - 5067
(2015/11/03)
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- CROSS METATHESIS APPROACH TO C11-C13 FATTY-CHAIN AMINO ESTERS FORM OLEIC ACID DERIVATIVES
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A concise method of producing nylon 11, 12, or 13 precursors from oleic acid or an ester of oleic acid is described. The method involves cross-metathesis reactions as the key C-C bond formation step. Subsequent steps are provided to convert the metathesis product to the corresponding nylon precursors. Also provided are the products of the method.
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Paragraph 0059; 0060; 0061
(2016/05/24)
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- Cross metathesis of bio-sourced fatty nitriles with acrylonitrile
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We report the cross metathesis of two olefinic partners containing different types of nitrile functionality. Thus, cross metathesis of fatty nitriles with acrylonitrile have been achieved with olefin metathesis ruthenium catalysts. 10-Undecenenitrile provides 2-dodecenedinitrile with a high turnover number of 13,280 in the green solvent, diethyl carbonate. Cross metathesis with the internal carbon-carbon double bond of oleonitrile gave the expected products, and the cleavage of the internal double bond proved to be more difficult probably owing to faster catalyst decomposition. Graphical abstract: [Figure not available: see fulltext.]
- Bidange, Johan,Fischmeister, Cédric,Bruneau, Christian,Dubois, Jean-Luc,Couturier, Jean-Luc
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p. 1107 - 1113
(2015/06/22)
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- Synthesis of α,β-unsaturated aldehydes and nitriles via cross-metathesis reactions using Grubbs' catalysts
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A series of α,β-unsaturated aldehydes and nitriles of significant interest in the fragrance industry have been prepared using Grubbs' catalysts in cross-metathesis reactions of electron-deficient olefins (i.e., acrolein, crotonaldehyde, methacrolein, and acrylonitrile) with various 1-alkenes, including 1-decene, 1-octene, 1-hexene and 2-allyloxy-6-methylheptane. The latter is of particular interest, as it has not previously being used as a substrate in cross-metathesis reactions and allows access to valuable intermediates for the synthesis of new fragrances. Most reactions gave good selectivity of the desired CM product (≥90%). Detailed optimisation and mechanistic studies have been performed on the cross-metathesis of acrolein with 1-decene. Recycling of the catalyst has been attempted using ionic liquids.
- Rountree, Sandra M.,Taylor, Sarah F.R.,Hardacre, Christopher,Lagunas, M. Cristina,Davey, Paul N.
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- Combined transition-metal- and organocatalysis: An atom economic C3 homologation of alkenes to carbonyl and carboxylic compounds
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A combination of regioselective room-temperature/ambient-pressure hydroformylation (transitionmetal catalysis) and decarboxylative Knoevenagel reactions (organocatalysis) allowed for the development of an efficient, one-pot C3 homologation of terminal alkenes to (E)-α,β-unsaturated acids and esters, (E)-β,γ-unsaturated acids, (E)-α-cyano acrylic acids, and α,β-unsaturated nitriles. All reactions proceed under mild conditions, tolerate a variety of functional groups, and furnish unsaturated carbonyl compounds in good yields and with excellent regioand stereocontrol. Further, an iterative C2 homologation of (E)-α,β-unsaturated carboxylic acids is possible through a combination of decarboxylative hydroformylation employing a supramolecular catalyst followed by decarboxylative Knoevenagel condensation with an organocatalyst.
- Kemme, Susanne T.,Smejkal, Tomas,Breit, Bernhard
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supporting information; experimental part
p. 3423 - 3433
(2010/06/21)
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- Rhenium(VII) oxo complexes as extremely active catalysts in the dehydration of primary amides and aldoximes to nitriles
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An economical and environmentally benign process for the preparation of nitriles by the dehydration of primary amides and aldoximes is catalyzed by rhenium(VII) oxo complexes such as perrhenic acid and trimethylsilylperrhenate (see scheme). The reaction proceeds at azeotropic reflux (with the removal of water) under essentially neutral conditions.
- Ishihara, Kazuaki,Furuya, Yoshiro,Yamamoto, Hisashi
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p. 2983 - 2986
(2007/10/03)
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- A Convenient Synthesis of α,β-Unsaturated Nitriles
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α,β-Unsaturated nitriles were synthesized by the reaction of aldehydes with bromoacetonitrile promoted by tri-n-butylphosphine and zinc.
- Zheng, Jianhua,Yu, Yang,Shen, Yanchang
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p. 3277 - 3282
(2007/10/02)
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- SYNTHESIS OF α,β-UNSATURATED NITRILES BY REACTION OF HALOACETONITRILE WITH CARBONYL COMPOUNDS MEDIATED BY TRI-n-BUTYLSTIBINE
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α,β-Unsaturated nitriles were synthesized by the reaction of haloacetonitriles with carbonyl compounds mediated by tri-n-butylstibine in excellent yields.
- Huang, Yao-Zeng,Shen, Yanchang,Chen, Chen
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- A REGIOSPECIFIC METHOD FOR THE HYDROCYANATION OF OLEFINS
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A convenient method for the anti-Markovnikov hydrocyanation of olefins utilizing organozirconium chemistry has been developed.This method has been shown to tolerate a wide range of functionality in the substrate olefin.
- Buchwald, Stephen L.,LaMaire, Susan J.
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p. 295 - 298
(2007/10/02)
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