279214-81-2Relevant academic research and scientific papers
Gold(I)-, palladium(II)-, platinum(II)-, and mercury(II)-catalysed spirocyclization of 1,3-enynediols: Reaction scope
Zhdanko, Alexander,Maier, Martin E.
supporting information, p. 3411 - 3422 (2014/06/09)
The spirocyclization of different 1,3-enynediols was investigated. The reaction was only efficient for the synthesis of [5,6]-spiroacetals. In this case, the reaction was characterized by almost quantitative yields, short reaction times, and low catalyst loadings (0.5-1%). When the synthesis of [6,6]-spiroacetals was attempted, the reaction suffered from poor regioselectivity and a higher propensity of the intermediate dienol ethers to decompose under the acidic conditions, and it became no longer viable. But it is possible to generate the dienol ethers cleanly under milder conditions as a mixture of regioisomers. This striking difference in reaction efficiency was explained by the unstable dienol ethers cyclizing more quickly to give [5,6]-spiroacetals than to give [6,6]-spiroacetals. In this study, the successful application of a new cationic palladium pincer complex for electrophilic alkyne activation at room temperature has been demonstrated for the first time. Copyright
Homocoupling of benzyl halides catalyzed by POCOP-nickel pincer complexes
Chen, Tao,Yang, Limin,Li, Liang,Huang, Kuo-Wei
experimental part, p. 6152 - 6157 (2012/08/29)
Two types of POCOP-nickel(II) pincer complexes were prepared by mixing POCOP pincer ligands and NiX2 in toluene at reflux. The resulting nickel complexes efficiently catalyze the homocoupling reactions of benzyl halides in the presence of zinc. The coupled products were obtained in excellent to quantitative yields.
The impact of P-substituents on the structures, spectroscopic properties, and reactivities of POCOP-type pincer complexes of nickel(II)
Salah, Abderrahmen B.,Zargarian, Davit
experimental part, p. 8977 - 8985 (2011/10/12)
The room temperature reaction of NiBr2(NCCH3) x with the pincer-type ligand POCHOPPh gave the new pincer complex (POCOPPh)NiBr (1, POCOPPh = κP, κC, κP-2,6-{Ph2PO} 2C6H3). Complex 1 reacts with AgX to give the analogous Ni-X derivatives (X = CN, 2; OSO2CF3, 3; OC(O)CH3, 4; ONO2, 5), whereas complex 3 reacts with phenylacetylene and NEt3 to give the Ni-CCPh derivative 6. On the other hand, reaction of 1 or 3 with RLi or RMgI did not afford the desired Ni-R derivatives, giving instead the corresponding iodo and hydroxo derivatives. Complexes 1-6 have been characterized by NMR, IR, and UV-Vis spectroscopy and X-ray crystallography. The solid state structural and IR data indicate that Ni-Csp interaction is dominated by ligand-to-metal σ-donation in 2 and 6. Cyclic voltammetry measurements indicate that complexes 3 and 4 display reversible redox behaviour (NiII/NiIII); comparison of the E01/2 values for these complexes and their POCOPi-Pr analogues shows that both the X ligands and the P-substituent have a considerable impact on the ease of oxidation in this family of complexes. The Royal Society of Chemistry 2011.
Palladium bis(phosphinite) 'PCP'-pincer complexes and their application as catalysts in the Suzuki reaction
Bedford,Draper,Scully,Welch
, p. 745 - 747 (2007/10/03)
Palladium complexes of inexpensive, easily synthesised his(phosphinite) 'PCP'-pincer ligands show good activity in the Suzuki coupling of deactivated and sterically hindered aryl bromides.
