65739-40-4Relevant academic research and scientific papers
Dicarbonylrhodium(I) complexes of bipyridine ligands with proximate H-bonding substituents and their application in methyl acetate carbonylation
Conifer, Christopher M.,Law, David J.,Sunley, Glenn J.,Haynes, Anthony,Wells, John R.,White, Andrew J. P.,Britovsek, George J. P.
, p. 3511 - 3522 (2011)
A series of cationic cis-dicarbonylrhodium(I) complexes [Rh(L)(CO) 2]SbF6 has been prepared containing 2,2′-bipyridine ligands with proximate H-bonding substituents R in the 6- and 6′-position (R = OH, NH2, COOEt and PO(OEt)2). The solid-state structures have been determined by X-ray crystallography for the complexes where R = OH, NH2 and COOEt. The molecular structures have revealed metal-metal and π-π interactions between the square-planar complexes resulting in the formation of molecular chains in the solid state. IR studies on the reaction of [Rh(bipy)(CO)2]SbF6 with MeI have shown the formation of a neutral complex [RhI(CO)(bipy)], which undergoes oxidative addition of MeI much faster than the cationic complex [Rh(bipy)(CO) 2]+. Although all complexes show good activities for the carbonylation of methyl acetate, this is believed to be due to their instability and the formation of [RhI2(CO)2]- under the reaction conditions.
Correlation between the Structure and Catalytic Activity of [Cp*Rh(Substituted Bipyridine)] Complexes for NADH Regeneration
Ganesan, Vinothkumar,Sivanesan, Dharmalingam,Yoon, Sungho
supporting information, p. 1366 - 1374 (2017/02/15)
A series of water-soluble half-sandwich [Cp*RhIII(N^N)Cl]+ (Cp* = pentamethylcyclopentadiene, N^N-substituted 2,2′-bipyridine) complexes containing electron-donating substituents around the 2,2′-bipyridyl ligand were synthesized and fully characterized for the regioselective reduction of nicotinamide coenzyme (NAD+). The influence of the positional effect of the substituents on the structural, electrochemical, and catalytic properties of the catalyst was systematically studied in detail. The catalytic efficiency of the substituted bipyridine Cp*RhIII complexes are inversely correlated with their redox potentials. The 5,5′-substituted bipyridine Cp*RhIII complex, which had the lowest reduction potential, most effectively regenerated NADH with a turnover frequency of 1100 h-1. Detailed kinetic studies on the generation of intermediate(s) provide valuable mechanistic insight into this catalytic cycle and help to direct the future design strategy of corresponding catalysts.
Design and synthesis of new Ru-complexes as potential photo-sensitizers: Experimental and TD-DFT insights
Sharmoukh,Hassan, Walid M. I.,Gros, Philippe C.,Allam, Nageh K.
, p. 69647 - 69657 (2016/08/05)
We report density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations on a novel organic ligand and a novel class of ruthenium complexes; cis-RuL2X2 with L = 2,2′-bipyridine-6,6′-bis ethyl ester phosphonate and phosphonic acid, X = Cl, CN or NCS. The calculations show that cis-configurations are more stable than the trans-counterparts. The DFT results have been used to help design such novel complexes for potential use as sensitizers. We demonstrate the opportunity to synthesize such complexes with high purity. The synthesis of these complexes relies on the preparation of the key intermediates cis-Ru(2,2′-bipyridine-6,6′-bisdiethyl ester phosphonate)Cl2. These complexes were characterized by 1H, 13C, and 31P NMR, elemental analysis and FTIR spectroscopy. The NCS complex shows the smallest optical band gap followed by the Cl and CN complexes, respectively, with the highest performance upon use as a sensitizer in dye-sensitized solar cells.
Na2(smbipy) - A bipyridine-derived ligand with chelating sulfonate tags and its 3d metal complexes
Oelkers, Benjamin
, p. 5838 - 5848 (2015/02/02)
The sulfonated bipyridine derivative disodium 6,6′-bis(sulfonatomethyl)-2,2′-bipyridine [Na2(smbipy)] was synthesized, and its complexation behaviour towards divalent 3d metals in aqueous solution was explored. The complexes of late 3d metals [M(smbipy)(H2O)2]·H2O (M = Co, Ni, Zn) and [Cu(smbipy)(H2O)] are sparingly soluble in water, and their crystal structures show fourfold equatorial coordination (κ4N,N',O,O') of the smbipy ligand. Ammonia-rich solutions of the NiII and CuII aqua complexes yield the decomplexation products [Ni(NH3)6](smbipy), [Ni(NH3)5(H2O)](smbipy) and [Cu(NH3)4](smbipy)·2H2O. Buffered solutions with a reduced ammonia content lead to [Ni(smbipy)(NH3)2] and [Cu(smbipy)(NH3)3]·2H2O, and the latter shows twofold coordination of the smbipy ligand through the nitrogen atoms only (κ2N,N'). When nearly quantitative amounts of ammonia are applied, two closely related complexes with the core motif [(smbipy)Cu(μ-OH)2Cu] form. Crystal structures of all complexes were obtained, and their features are discussed.
Diastereoselective self-assembly of a homochiral europium triangle from a bipyoxazoline-carboxylate ligand
Bozoklu, Guelay,Marchal, Claire,Gateau, Christelle,Pecaut, Jacques,Imbert, Daniel,Mazzanti, Marinella
supporting information; experimental part, p. 6159 - 6163 (2010/07/07)
(Figure Presented) A homochiral triangle: An enantiopure europium triangle selectively selfassembles from a new bipyoxazolinecarboxylate ligand in a concentrationdependent process (see scheme).
Facile synthesis of polypyridine esters: A route to functionalized aldehydes
El-Ghayoury,Ziessel
, p. 7757 - 7763 (2007/10/03)
A wide range of ester-substituted oligopyridines, based on pyridine, 1,8-naphthyridine, 1,10-phenanthroline, 2,2'-bipyridine, and 2,2':6',6-terpyridine units, has been synthesized and fully characterized. The principal reaction involves the palladium(0)-catalyzed carboalkoxylation of the bromo-, chloro- or triflate-substituted pyridine unit with carbon monoxide in the presence of a primary alcohol as nucleophile and a tertiary amine as base. Monofunctionalization of disubstituted compounds is realized by reaction in ethanol under mild conditions (70 °C, 1 atm CO). Stepwise reduction of selected esters with sodium borohydride, followed by Swern oxidation, affords the corresponding carbaldehydes in good yield. Several products are reported for the first time. The synthetic methods reported herein represent a valuable approach to the large-scale preparation of ester-functionalized oligopyridines that can be subsequently transformed to the corresponding alcohols or acids. These procedures also provide a practical methodology to the rational design of ligands bearing different kinds of functionalities.
