108915-08-8Relevant articles and documents
Copper(II) complexes of pyridine-oxazoline (Pyox) ligands: Coordination chemistry, ligand stability, and catalysis
Hallett, Andrew J.,O'Brien, Thomas M.,Carter, Emma,Kariuki, Benson M.,Murphy, Damien M.,Ward, Benjamin D.
, p. 86 - 94 (2015/12/01)
The coordination chemistry of copper(II) complexes bearing pyridine-oxazoline ("Pyox") ligands has been studied, with an aim of investigating their catalytic ability. Interestingly, the stability of the coordinated ligands has been shown to be much less than previously assumed: hydrolysis of the ligands by fortuitous water gives rise to 2-pyridine carboxylate formation, which encapsulate the copper in a two-dimensional coordination polymer 3. The complexes [Cu(R-Pyox)(NCMe)2(ClO4)2] {R = benzyl (Bn) 2a, phenyl (Ph) 2b, isopropyl (iPr) 2c} have been prepared, of which the benzyl derivative has been analysed by CW EPR spectroscopy. The complex [Cu(Bn-Pyox)(NCMe)2(ClO4)2] and the afore-mentioned coordination polymer have been crystallographically characterised. The performance of complexes 2a-c in the asymmetric allylic oxidation of cyclohexene is described.
Palladium-Catalyzed C-2 C-H Heteroarylation of Chiral Oxazolines: Diverse Synthesis of Chiral Oxazoline Ligands
Xi, Tuo,Mei, Yuncai,Lu, Zhan
supporting information, p. 5939 - 5941 (2016/01/09)
A direct, efficient, and practical protocol to install a chiral oxazoline unit onto aryl/heteroaryl rings via palladium-catalyzed C-H functionalization of 2-positions of oxazolines with a variety of halides using dppe as the ligand has been developed. Var
Parallel screening of asymmetric bidentate ligands in zinc catalyzed transfer hydrogenation
Zaman, Tariq,Nasir, Habib,Bergin, Enda
, p. 85 - 90 (2014/05/06)
Development in the field of asymmetric catalysis is driven by the importance of stereochemically pure compounds in the field of pharmaceutical industry, agrochemicals and flavors. The unpredictable results given by new catalysts make the design of effecti
Application of rapidly generated bidentate ligand libraries to zinc catalyzed reductions
Zaman, Tariq,Frauenlob, Robin,McCarthy, Robert,Walsh, Carolyn M.,Bergin, Enda
, p. 159 - 166 (2012/11/13)
A methodology for the combinatorial synthesis of bidentate ligands - allowing direct screening of reaction products without the need for isolation or purification - has been employed in a zinc catalyzed hydrosilylation. This reaction allowed the robustness of the methodology to be examined, by employing it in a challenging case where the metal complex is not pre-formed prior to catalysis. Four different ligand families have been examined: imines, aminals, bis-imines and oxazolines and related compounds, with a small library of each type produced and directly screened in the reaction. Three ligands providing enantioselectivities of 50% or more in this very challenging reaction were identified, and ees and conversions were equivalent whether the ligand was obtained as a crude mixture from a library synthesis or as an isolated, purified compound.
Rapid, in situ synthesis of bidentate ligands: Chromatography-free generation of catalyst libraries
Frauenlob, Robin,McCormack, Martha M.,Walsh, Carolyn M.,Bergin, Enda
supporting information; experimental part, p. 6934 - 6937 (2011/11/04)
The parallel synthesis of chiral bidentate ligands and their subsequent use in situ for a catalytic process is described. The ligands thus prepared gave comparable results to those obtained when the ligands were synthesized and purified by conventional means. This includes oxazolines and other compounds of similar complexity, meaning that for the first time these valuable compounds have been brought into the field of combinatorial catalysis.
Synthesis and evaluation of the in vitro DNA-binding properties of chiral cis-dichloro(pyridyloxazoline)platinum(II) complexes
Dodd, David W.,Toews, Heather E.,Trevail, Michael J.,Jennings, Michael C.,Hudson, Robert H.E.,Jones, Nathan D.
scheme or table, p. 321 - 327 (2009/10/23)
A series of chiral cis-dichloro(pyridyloxazoline)platinum(II) and palladium(II) complexes were synthesized and their reactivity towards a defined sequence of single-stranded and double-stranded DNA was investigated in comparison to cisplatin. The compounds differed in the nature and absolute configuration of the substituent at the C4 position of the oxazoline ring. The DNA-binding ability of these compounds was evaluated by HPLC analysis, post metal exposure, of enzymatic digests of an undecamer duplex containing one putative metallation site. Polyacrylamide gel electrophoresis (PAGE) and thermal denaturation confirmed the results of the HPLC analysis, which showed that the stereochemistry and character of the substituent at the C4 position of the oxazoline ring had little effect on DNA binding, possibly due to the formation of monofunctional adducts.
Asymmetric Catalysis, 45. - Enantioselective Hydrosilylation of Ketones with 2/Pyridinyloxazoline Catalysts
Brunner, Henri,Obermann, Uwe
, p. 499 - 508 (2007/10/02)
21 optically active 2-(2-pyridinyl)oxazolines are synthesized from 2-cyanopyridine and optically pure amino alcohols.The new pyridinyloxazolines are used as cocatalysts together with 2 as homogeneous in situ catalysts in the enantioselective hydrosilylation of prochiral ketones with diphenylsilane.After hydrolysis, 1-phenylethanol is produced in 83.4percent ee from acetophenone.Another three ketones are included into these investigations.The optical purity depends on the rhodium/ligand, rhodium/ketone, and ketone/silane ratio as well as on the solvent.Compared with other organic solvents, hydrosilylations in the solvent CCl4 without exceptions result in better chemical yields and optical purities as consequence of a change in the catalytically active species due to oxidative addition of CCl4. - Keywords: Enantioselective hydrosilylation/ Optically active secondary alcohols/ Rhodium/ pyridinyloxazoline catalysts
