16851-72-2Relevant articles and documents
η6-mesityl,η1-imidazolinylidene-carbene- ruthenium(II) complexes: Catalytic activity of their allenylidene derivatives in alkene metathesis and cycloisomerisation reactions
Cetinkaya, Bekir,Demir, Serpil,Oezdemir, Ismail,Toupet, Loic,Semeril, David,Bruneau, Christian,Dixneuf, Pierre H.
, p. 2323 - 2330 (2003)
The reaction of electron-rich carbene-precursor olefins containing two imidazolinylidene moieties [(2,4,6- Me3C6H2CH2)NCH2 CH2N(R)C=]2 (2a: R = CH2CH2OMe, 2
Organic-inorganic hybrid silica material derived from a monosilylated Grubbs-Hoveyda ruthenium carbene as a recyclable metathesis catalyst
Borja, Guadalupe,Pleixats, Roser,Alibes, Ramon,Cattoen, Xavier,Chi Man, Michel Wong
, p. 5756 - 5767 (2010)
The synthesis of a monosilylated Grubbs-Hoveyda ruthenium alkylidene complex is described, as well as the preparation and characterization of the corresponding material by sol-gel cogelification with tetraethoxysilane (TEOS) and the assay of this recyclab
Immobilization of grubbs catalyst as supported ionic liquid catalyst (Ru-SILC)
Hagiwara, Hisahiro,Okunaka, Naotaro,Hoshi, Takashi,Suzuki, Toshio
, p. 1813 - 1816 (2008)
Grubbs olefin metathesis catalyst was immobilized as a ruthenium-supported ionic liquid catalyst (Ru-SILC) in pores of amorphous alumina with the aid of ionic liquid [hmim]PF6. This Ru-SILC was effective for various olefin metathesis reactions
Olefin metathesis catalyst bearing a chelating phosphine ligand
Lexer, Christina,Burtscher, Daniel,Perner, Bernhard,Tzur, Eyal,Lemcoff, N. Gabriel,Slugovc, Christian
, p. 2466 - 2470 (2011)
An improved synthetic procedure for the complex (SPY-5-34)-dichloro- (κ2(C,P)-diphenyl-(2-benzylidene)-phosphine)-(1,3-bis(2,4, 6-trimethylphenyl)-4,5-dihydro-imidazol-2-ylidene)-ruthenium (2) was elaborated and the title compound was tested as
Mixed N-heterocyclic carbene/phosphite ruthenium complexes: Towards a new generation of olefin metathesis catalysts
Bantreil, Xavier,Schmid, Thibault E.,Randall, Rebecca A. M.,Slawin, Alexandra M. Z.,Cazin, Catherine S. J.
, p. 7115 - 7117 (2010)
The synthesis, characterisation and catalytic behaviour of ruthenium indenylidene complexes bearing an N-heterocyclic carbene and triisopropylphosphite are described.
Ruthenium-catalyzed olefin metathesis in ionic liquids
Buijsman, Rogier C.,Van Vuuren, Elizabeth,Sterrenburg, Jan Gerard
, p. 3785 - 3787 (2001)
Figure presented Ionic liquid 1-butyl-3-methylimidazoliumhexafluorophosphate ([bmim]PF6) is described as an effective medium for ring-closing metathesis (RCM) using Grubbs catalysts. When [bmim]PF6 was used as solvent, the RCM showed
Allenyl esters as quenching agents for ruthenium olefin metathesis catalysts
Roy, Animesh,Silvestri, Maximilian A.,Hall, Robert A.,Lepore, Salvatore D.
, p. 106 - 108 (2017)
In the attempt to synthesize substituted allenyl esters through a metathesis coupling of unsubstituted allenyl esters and alkenes using a variety of ruthenium catalysts, it was discovered that allenyl esters themselves cleanly arrested the activity of the catalysts. Further studies suggests possible utility of allene esters as general quenching agents for metathesis reactions. To explore this idea, several representative olefin metathesis reactions, including ring closing, were successfully terminated by the addition of simple allenyl esters for more convenient purification.
Ruthenium catalysts bearing chelating carboxylate ligands: application to metathesis reactions in water
Gawin, Rafa?,Czarnecka, Patrycja,Grela, Karol
, p. 1051 - 1056 (2010)
The novel catalytic system, composed of a ruthenium alkylidene containing a surfactant fragment in the catalysts molecule, is reported. Ring closing metathesis and cross metathesis reactions proceed efficiently in neat water at room temperature, in air, without need of adding an external surfactant.
Non covalent immobilization of pyrene-tagged ruthenium complexes onto graphene surfaces for recycling in olefin metathesis reactions
Nasrallah, Houssein,Germain, Stéphane,Queval, Pierre,Bouvier, Caroline,Mauduit, Marc,Crévisy, Christophe,Schulz, Emmanuelle
, p. 136 - 146 (2016)
Synthesis of Hoveyda-type ruthenium complexes, modified by pyrene tags on the NHC ligand and/or the benzylidene moiety, is described. Thanks to non-covalent π-π interactions these new complexes were immobilized on carbon supports [reduced graphene oxide (rGO) or graphene] and their activity and recoverability for metatheses reactions have been studied. A SIPr-based complex possessing the pyrene function on the benzylidene ligand (C2) delivered the best results for the ring closing metathesis of diethyldiallyl malonate as benchmark reaction. The presence of additional pyrene-functionalized styrenyl-ether as ligand to the rGO-supported catalyst (C2/L@rGO) noticeably improved the recycling procedure allowing supplementary efficient catalytic runs. This may be due either to a facilitated boomerang effect or to a gradual release of the active species in solution. Finally, catalyst C2/L@rGO was proven to be successfully used to promote metathesis reactions in a multisubstrate procedure, the same supported-catalyst batch being successively engaged to transform three different substrates, in diene and ene-yne RCM reactions.
A dormant ruthenium catalyst bearing a chelating carboxylate ligand: In situ activation and application in metathesis reactions
Gawin, Rafal,Makal, Anna,Wozniak, Krzysztof,Mauduit, Marc,Grela, Karol
, p. 7206 - 7209 (2007)
(Chemical Equation Presented) Sleeping beauty: A dormant catalyst, 1, can be activated in situ by various acids (HA) to form complexes 2 of high activity in olefin metathesis. After the reaction and when subjected to silica gel chromatography, these catalysts are readily transformed back into 1. This system shows a high degree of tunability and excellent applicability in model metathesis reactions.
Nucleophile dependent formation of 6- and 7-membered: N -heterocycles by platinum-catalysed cyclisation of 1,5-bisallenes
Quirós, María Teresa,Hurtado-Rodrigo, César,Mu?oz, María Paz
, p. 6731 - 6734 (2017)
An unprecedented Pt-catalysed cyclisation of N-tethered 1,5-bisallenes in the presence of oxygen nucleophiles is reported, where formation of 6- or 7-membered rings is driven by the choice of nucleophile and the mechanism dictated by the nucleophile and the electronic properties of the bisallene. The reaction in the presence of alcohols gives preferentially vinyltetrahydropyridines with an extra alkoxy group and Pt-H as the active species in the catalytic cycle, while formation of di- and tetrahydroazepines with an extra hydroxyl group is favoured when water is used as nucleophile, via nucleophilic attack/carbocyclization as the favoured pathway. The products obtained are frequently found in the core of natural products with important biological activities, so understanding this complex mechanistic behaviour and exploiting this new methodology will have a big impact in organic synthesis and organometallic chemistry.
Fluorous phase-transfer activation of catalysts: Application of a new rate-enhancement strategy to alkene metathesis
Correa Da Costa, Rosenildo,Gladysz
, p. 2619 - 2621 (2006)
Reactions of the bis(pyridine) complex (H2IMes)(Py) 2(Cl)2Ru(=CHPh) and fluorous phosphines P(CH 2CH2Rfn)3 (n = a, 6; b, 8; c, 10; Rfn = (CF2)n-1
Model studies towards kainic acid
Greenwood,Parsons
, p. 167 - 169 (2002)
A novel photochemical approach to the kainoid ring system is presented alongside model studies to demonstrate its feasibility.
Activated Hoveyda-Grubbs Olefin Metathesis Catalysts Derived from a Large Scale Produced Pharmaceutical Intermediate – Sildenafil Aldehyde
Monsigny, Louis,Pi?tkowski, Jakub,Trzybiński, Damian,Wo?niak, Krzysztof,Niena?towski, Tomasz,Kajetanowicz, Anna,Grela, Karol
supporting information, p. 4590 - 4604 (2021/08/13)
Two EWG-activated Hoveyda-Grubbs-type ruthenium complexes (Sil-II and Sil-II’) were obtained, characterized, and screened in a set of olefin metathesis reactions. These catalysts were conveniently synthesized from a commercially available pharmaceutical building block – Sildenafil aldehyde – in two steps only. Stability and catalytic activity tests disclosed that the bulkier NHC-ligand bearing catalyst Sil-II’ is visibly more stable and productive than its smaller NHC-analogue Sil-II. Good application profile of catalyst Sil-II’ was confirmed in a set of diverse metathesis reactions including ring-closing metathesis (RCM) and cross-metathesis (CM) of complex polyfunctional substrates of medicinal chemistry interest, including a challenging macrocyclization of the Pacritinib precursor. Compatibility of the new catalyst with various green solvents was checked and metathesis of Sildenafil and Tadalafil-based substrates was successfully conducted in acetone. The mechanism of Sil-II’ initiation has been investigated through kinetic experiments unveiling that the decrease of the steric hindrance of the chelating alkoxy moiety (from iPrO to EtO) favors the interchange initiation pathway over the typical dissociation pathway for other popular 2nd generation Hoveyda-Grubbs catalysts. (Figure presented.).
Synthetic method of 3-aminopyrrolidine hydrochloride
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Paragraph 0092-0095; 0099-0102, (2021/03/31)
The invention discloses a synthetic method of 3-aminopyrrolidine hydrochloride. The synthetic method comprises the steps: S1, carrying out cyclization reaction on a compound I and a compound II to obtain a compound III; S2, reacting the compound III under the action of hydrogen halide gas to obtain a compound IV; S3, reacting the compound IV with organic sulfonamide in the presence of alkali to obtain a compound V; and S4, reacting the compound V with acid to obtain a compound VI. According to the synthetic method of the 3-aminopyrrolidine hydrochloride, aryl and alkyl sulfonic groups are introduced to protect two amino groups, and during deprotection, a single reaction condition can be used, so that operation steps are effectively reduced; when benzyl is used for protecting ammonia, precious metal palladium and high-pressure catalytic hydrogenation are used for deprotection, the production cost is high, the operation risk is high, aryl and alkane sulfonic groups are used for protection, only acid is used for catalytic hydrolysis for deprotection, and the reaction condition is mild.
One-pot chemoenzymatic reactions in water enabled by micellar encapsulation
Adams, Nicholas P.,Bushi, Jurgen,Hastings, Courtney J.,Kolb, Samuel J.
, p. 6187 - 6193 (2020/10/18)
The use of micellar conditions to enable one-pot reactions involving both transition metal and enzymatic catalysts is reported. Representative enzymatic transformations under micellar conditions are unaffected by the presence of non-ionic surfactants, including designer surfactants such as TPGS-750-M. Furthermore, the presence of enzymes has a negligible effect on transition metal catalysis under micellar conditions in water. Finally, three one-pot chemoenzymatic reactions in water are reported in which the micelle-forming surfactant TPGS-750-M is a crucial factor for reaction efficiency.