247902-48-3Relevant academic research and scientific papers
Organoplatinum(ii) complexes containing chelating or bridging bis(N-heterocyclic carbene) ligands: Formation of a platinum(ii) carbonate complex by aerial CO2 fixation
Jamali, Sirous,Milic, Dalibor,Kia, Reza,Mazloomi, Zahra,Abdolahi, Hallimeh
, p. 9362 - 9365 (2011)
The preparation of two new bis(N-heterocyclic carbene) platinum(ii) complexes, in which NHC rings are joined by a CH2 linker group, is described. While, the chelate complex [PtMe2(bis-NHC1)], 1, was formed with large tert-butyl wingtips, the iso-propyl N-substituent analogue favors formation of the cluster complex [Pt2Me4(μ- SMe2)(μ-bis-NHC2)]2(μ-Ag2Br2), 2, in which two binuclear platinum(ii) complexes are linked together by an Ag2Br2 unit. The chelating platinum complex 1 undergoes aerial CO2 fixation and forms platinum(ii) carbonate complex [Pt(CO3)(bis-NHC1)], 3.
Carbene-anchored/pendent-imidazolium species as precursors to di-N-heterocyclic carbene-bridged mixed-metal complexes
Zamora, Matthew T.,Ferguson, Michael J.,McDonald, Robert,Cowie, Martin
, p. 7269 - 7287 (2009)
Reaction of a series of linked diimidazolium dibromide salts with one-half equivalent of [Rh(μ-OAc)(COD)]2 under reflux conditions generates a series of carbene-anchored/pendent-imidazolium complexes, [RhBr(COD)( RC(H)-η1-Ceth)][Br] (MeC(H)- η1-Ceth = ethylene[(N-methyl)imidazolium][(N-methyl) imidazole-2-ylidene] and tBuC(H)-η1-Ceth = ethylene[(N-tert-butyl)imidazolium][(N-tert-butyl)imidazole-2-ylidene]) via deprotonation of one end of the diimidazolium salt and coordination of the resulting carbene to Rh. Reaction of these complexes with carbon monoxide or the appropriate diphosphine yields either [RhBr(CO)2( RC(H)-η1-Ceth)][Br] (R = Me, tBu) or [RhBr(P∩P)(MeC(H)- η1-Ceth)][Br] (P∩P = Ph 2PCH2PPh2, Ph2PCH2CH 2PPh2, Et2PCH2PEt2), respectively. The resulting diphosphine complexes readily decompose in solution. A series of palladium complexes [PdI3-n(PR3) n(L)][I]n (n = 1,2) and [PdI(P∩P)(L)][I] 2 (L = tBuC(H)-η1-Cmeth, tBuC(H)-η1-Ceth; tBuC(H)- η1-Cmeth = methylene[(N-tert-butyl)imidazolium][(N- tert-butyl)imidazole-2-ylidene]), containing the linked NHC-imidazolium moiety, have also been prepared by reacting the triiodo complexes, [PdI 3(tBuC(H)-η1-Cmeth)] and [PdI3(tBuC(H)-η1-Ceth)] with several mono- and diphosphines. Attempts to generate mixed Rh/Pd complexes using Pd(OAc)2 to deprotonate the pendent arm of several of the above carbene-anchored/pendent-imidazolium complexes of Rh have proven unsuccessful. However, a targeted di-NHC-bridged heterobimetallic complex [PdI 2(PEt3)(μ-tBuCCmeth)RhI(COD)] (tBu CCmeth = 1,1′-methylene-3,3′-di-tert- butyldiimidazol-2,2′-diylidene) can be generated by deprotonation of the imidazolium group in [PdI2(PEt3)(tBuC(H)- η1-Cmeth)][I] using half an equivalent of [Rh(μ-OAc)(COD)]2. The X-ray structure determination of this Pd/Rh complex confirms the dicarbene-bridged formulation and shows a metal-metal separation of approximately 6.2 A. Reaction of this Rh/Pd complex with CO yields the corresponding dicarbonyl product [PdI2(PEt 3)(μ-tBuCCmeth)RhI(CO)2] via replacement of the COD ligand. The related dicarbene-bridged Ir/Rh complex [IrBr(COD)(μ-tBuCCmeth)RhBr(COD)] can be generated by reaction of [IrBr(COD)(tBuC(H)-η1-Cmeth)] [Br] with [Rh(μ-OAc)(COD)]2, while the Pd/Ir complexes [PdI 2(PR3)(μ-tBuCCmeth)IrI(COD)] (PR3 = PPh3, PMe2Ph) can be generated by reaction of the monometallic [PdI2(PR3)( tBuC(H)-η1-Cmeth)][I] species with K[N(SiMe3)2] in the presence of [Ir(μ-Cl)(COD)] 2. The carbonyl analogues, [PdI2(PR3)(μ- tBuCCmeth)IrI(CO)2], can be generated via a gentle purge of CO gas. These di-NHC-bridged heterobimetallic species represent some of the first examples of this class and are the first involving palladium.
Bis-NHC chelate complexes of nickel(0) and platinum(0)
Brendel, Matthias,Braun, Carolin,Rominger, Frank,Hofmann, Peter
, p. 8741 - 8745 (2014)
For a long time d10-ML2 fragments have been known for their potential to activate unreactive bonds by oxidative addition. In the development of more active species, two approaches have proven successful: the use of strong σ-donating
USE OF PT-AND PD-BIS-AND TETRA-CARBON COMPLEXES WITH BRIDGED CARBON LIGANDS IN OLEDS
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Page/Page column 10; 11, (2010/01/31)
The use of Pt- and Pd-bis- and tetracarbene complexes with bridged carbene ligands in organic light-emitting diodes, organic light-emitting diodes comprising at least one aforementioned Pt- or Pd-carbene complex, at least one transition metal-carbene comp
Bridged imidazolium salts used as precursors for chelating carbene complexes of palladium in the Mizoroki-Heck reaction
Scherg, Tobias,Schneider, Sabine K.,Frey, Guido D.,Schwarz, Jürgen,Herdtweck, Eberhardt,Herrmann, Wolfgang A.
, p. 2894 - 2907 (2008/03/13)
A variety of chiral and achiral imidazolium salts is synthesized. Methylene-, ethylene-, propylene- and pyridinyl-bridged bis(imidazolium) halides are used to generate the respective free chelating carbenes. The synthesis of palladium complexes of general formula [cis-CH2{NC(H)=C(H)N(R)C} 2PdX2] with these chelating N-heterocyclic carbene ligands is reported. Structural proofs of complexes 28 and 46 are represented by X-ray diffraction studies. Catalytic applications in the Mizoroki-Heck reaction are presented. Georg Thieme Verlag Stuttgart.
