6894-19-5Relevant articles and documents
Synthesis and catalytic application of Pd complex catalysts: Atom-efficient cross-coupling of triarylbismuthines with haloarenes and acid chlorides under mild conditions
Jadhav,Pardeshi
, (2017/03/24)
Palladium-catalysed cross-coupling reactions are some of the most frequently used synthetic tools for the construction of new carbon–carbon bonds in organic synthesis. In the work presented, Pd(II) complex catalysts were synthesized from palladium chloride and nitrogen donor ligands as the precursors. Infrared and 1H NMR spectroscopic analyses showed that the palladium complexes were formed in the bidentate mode to the palladium centre. The resultant Pd(II) complexes were tested as catalysts for the coupling of organobismuth(III) compounds with aryl and acid halides leading to excellent yields with high turnover frequency values. The catalysts were stable under the reaction conditions and no degradation was noticed even at 150°C for one of the catalysts. The reaction proceeds via an aryl palladium complex formed by transmetallation reaction between catalyst and Ar3Bi. The whole synthetic transformation has high atom economy as all three aryl groups attached to bismuth are efficiently transferred to the electrophilic partner.
Pd(II) catalyzed transformation of Schiff bases in complexes of the type trans-[PdCl2(NH2Ar-X)2] (X = H, CH3, Cl): Reactivity with aldehydes and Heck coupling reaction
Kumari, Niraj,Yadav, Vinod Kumar,Zalis, Stanislav,Mishra, Lallan
, p. 554 - 563 (2012/06/30)
Schiff bases of type (R-Ph-N=CH-Ph-CH=N-Ph-R), where, R = H (L 1), CH3 (L2) and Cl (L3), in presence of cis-[Pd(en)Cl2] or [Pd(DMSO)2Cl2] (en = 1,2-diaminoethane, DMSO = dimethylsulphoxide) give trans-[PdCl 2(NH2Ph)2] (1), trans-[PdCl2(NH 2PhCH3)2] (2) and trans-[PdCl 2(NH2PhCl)2] (3). The complexes are characterized using spectroscopic (IR, UV-vis and NMR) and X-diffraction techniques. The H-bonding interaction generates multinuclear supramolecular structure in complex (2) and (3). Complex (1) on reaction with benzaldehyde, salicylaldehyde and 4-carboxybenzaldehyde yields complexes of the type [PdCl2(PhN=CHPh)2] (4), [Pd(PhN=CHPhO)2] (5) and [PdCl2(PhN=CHPhCOOH)2] (6) respectively. The structures have been optimized using density functional theory at B3LYP level. Heck coupling reactions of bromobenzene with acrylonitrile and bromobenzene with ethyl acrylate in the presence of complexes (1), (2) and (3) have been carried out separately.
Cyclopalladation of meta -(diphenylthiophosphoryloxy)benzaldimines: NCS and unexpected NCO 5,6-membered pincer palladium complexes
Kozlov,Aleksanyan,Nelyubina, Yu. V.,Lyssenko,Vasilev,Petrovskii,Odinets
, p. 2054 - 2062 (2010/06/18)
Unsymmetrical NCS-pincer ligands of a new type, namely, m-(diphenylthiophosphoryloxy)benzaldimines 3 (1-[Ph2P(S)O]-3-[CH - NR]-C6H4, R = OMe (3a), Ph (3b), tBu (3c)), were obtained in two steps starting from commercially available 3-hydroxybenzaldehyde. These ligands easily underwent cyclopalladation at the C-2 position of the central benzene ring in the reaction with PdCl 2(PhCN)2 in benzene or benzene-methanol solutions to afford the corresponding hybrid pincer complexes 4a-c with five- and six-membered fused metallacycles in moderate to good yields. The same reaction in dichloromethane followed by treatment with alcohol resulted in unexpected formation of the related NCO-palladacycles 5a,b, along with the above NCS-complexes. Complexes 5 present the products of formal oxidation of the P - S group in the starting ligand, which apparently proceeds in the metal ion coordination sphere. Realization of κ3-NCS and κ3-NCO coordination in 4a-c and 5a,b, respectively, was unambiguously confirmed by X-ray diffraction analysis as well as multinuclear (1H, 13C, 31P) NMR, IR, and Raman spectroscopy. The NCS-pincer complexes 4a-c demonstrated excellent catalytic activity for the Suzuki cross-coupling reactions of aryl halides with phenylboronic acid.
