Heterocyclic carbene
Platinum(II) n heterocyclic carbene complexes : coordination and cyclometallation
... stabilised heterocyclic carbene (NHC) ligand has progressed from being an academic curiosity to its present ubiquity: it is now considered as a versatile ligand that is often used in preference to the more ...
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Coordination chemistry of N heterocyclic carbene and thione functionalised calix[4]arene ligands
... free carbene 2a was readily formed in solution by addition of strong bases, characterised in situ and trapped by addition of elemental sulfur resulting in the formation of the imidazol-2-thione adduct ...
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N heterocyclic carbene rhodium(I) and iridium(I) hydroxide complexes
... the carbene via cooperative inductive and mesomeric ...the carbene carbon and hence the existence of a zwitterionic type structure with the negative charge localised at the ...the carbene centre is ...
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Examination of catalytically relevant palladium `N` Heterocyclic carbene complexes
... Identical conditions from these trials were used to examine the catalytic activity of 20a, in which 20.1 mg of 20a was dissolved in 50 mL of methanol under inert atmosphere and transferred to a Parr reactor. The reactor ...
246
BIOLOGICAL ACTIVITY EVALUATION OF NOVEL N HETEROCYCLIC CARBENE PRECURSORS
... Department of Chemistry 2 , Faculty of Arts and Sciences, Inönü University, 44280 Malatya, Turkey. ABSTRACT: Five novel benzimidazolium salts were synthesized as N-heterocyclic carbene (NHC) precursors ...
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NEWLY DEVELOPED ANCHORED Ru(II) N HETEROCYCLIC CARBENE COMPLEX AND ITS APPLICATIONS
... N-heterocyclic carbene complexes represent a very useful family of organo-metallic complexes, which can catalyze a great deal of important reactions, among others: hydrogenation, hydrogen-transfer, ...
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Bidentate N Heterocyclic carbene complexes of group 13 trihydrides and trihalides
... coordination number greater than four, even in the presence of bis-phosphine ligands. These observations can be explained by the highly nucleophilic nature of the carbene ligands in these complexes, which ...
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Synthesis and Characterization of N Heterocyclic Carbene and their Complexes with Ni (II) and Studying their Biological Activity against Escherichia coli
... bond, carbene complexes give robust catalytic systems and so, a number of transition metal complexes of multidentate NHCs containing phosphorous, oxygen, and nitrogen functionalities have been ...
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Light stable silver N Heterocyclic carbene catalysts for the alkynylation of ketones in air
... aqueous process showcasing silver(I)/phosphine as an efficient system for such a transformation. In the latter case, long reactions times (1 to 2 days) were required and the reaction had to be conducted under an inert ...
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Investigation of the Role of Electrogenerated N Heterocyclic Carbene in the Staudinger Synthesis in Ionic Liquid
... One of the most studied and used class of ILs in or- ganic chemistry is the imidazolium based one, due to its air and water-stability, low cost and wide temperature window of the liquid phase [4,5]. Nevertheless, these ...
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Synthesis and reactivity studies of mono and diaurated species bearing N heterocyclic carbene ligands
... Next, we proceeded to examine the generality of our procedure (Table 2). We decided to test our new synthetic protocol on the imidazolium and imidazolidinium salts shown in Figure 1. We started our studies using ...
167
Versatile relay and cooperative palladium(0) N heterocyclic carbene/copper(I) N heterocyclic carbene catalysis for the synthesis of tri and tetrasubstituted alkenes
... : = 98:2. Under the optimized reaction conditions, the scope of this new one-pot relay coupling was investigated (Scheme 2). Several aryl bromides 6 and unsymmetrical alkynes 1 were tested. All products were obtained ...
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Backbone tuning in indenylidene ruthenium complexes bearing an unsaturated N heterocyclic carbene
... The use of N-heterocyclic carbenes (NHC) as spectator ligands in ruthenium-mediated olefin metathesis represents one of the most important breakthroughs in this field [1-8]. Mixed complexes bearing both a ...
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Tethered N-Heterocyclic Carbene-Carboranes: Unique Ligands that Exhibit Unprecedented and Versatile Coordination Modes at Rhodium
... N- Heterocyclic carbenes (NHCs) are excellent two electron donor ligands, with their steric and electronic properties being controlled and tuned through alteration of the N-substituents and backbone substituents ...
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Examining the validity and reliability of the Activities Specific Balance Confidence Scale 6 (ABC 6) in a diverse group of older adults
... The selective catalysis of triene cyclizations has often eluded chemist in the synthetic field. The cyclization yields promising products that contain unique functional groups, which are often difficult to access by ...
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Identifying the roles of amino acids, alcohols and 1,2-diamines as mediators in coupling of haloarenes to arenes
... Organic electron donors have been studied intensively in recent years. 48−60 These range from TTF 24 through TDAE 25 to more recent examples 28 − 32. In each case, an electron-rich alkene is present (shown in blue in ...
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Electrochemical flow-reactor for expedient synthesis of copper-N-heterocyclic carbene complexes
... Since their isolation in 1991, 1 N-heterocyclic carbenes (NHCs) have become ubiquitous in organometallic chemistry and catalysis, including hydrogenation, hydrosilylation, cross- coupling reactions and olefin ...
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Non classical anionic naked N heterocyclic carbenes: fundamental properties and emerging applications in synthesis and catalysis
... The most acidic proton in an NH,NR or NH,NH imidazolium salt is attached to the nitrogen atom, and not the C2 carbon. For this reason, the treatment of such a salt with base results in the regioselective deprotonation of ...
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Evaluation of an olefin metathesis pre catalyst with a bulky and electron rich N heterocyclic carbene
... measured (Table 2); and reaction with butyl vinyl ether which irreversibly forms a metathesis- inactive Fischer carbene species 37 under conditions where phosphine dissociation is rate-determining (Table 3). 15 ...
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Synthesis and characterisation of an N-heterocyclic carbene with spatially-defined steric impact
... The carbene features spatially-defined steric impact; two quadrants of the coordination sphere of the metal are left open and accessible, while the other two are blocked by diphenylmethyl ...new carbene has ...
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