62402-17-9Relevant academic research and scientific papers
Catecholase activity of mononuclear copper(II) complexes of tridentate 3N ligands in aqueous and aqueous micellar media: Influence of stereoelectronic factors on catalytic activity
Anitha, Natarajan,Saravanan, Natarajan,Ajaykamal, Tamilarasan,Suresh, Eringathodi,Palaniandavar, Mallayan
, p. 98 - 111 (2019)
A series of mononuclear copper(II) complexes of the type [Cu(L)Cl2] 1–6, where L is a tridentate 3 N ligand such as N-methyl-N′-(pyrid-2-ylmethyl)ethylenediamine (L1), N-ethyl-N′-(pyrid-2-ylmethyl)ethylenediamine (L2), N-phenyl-N′-(pyrid-2-ylmethyl)ethylenediamine (L3), N,N-dimethyl-N′-(pyrid-2-ylmethyl)ethylenediamine (L4), N,N-diethyl-N′-(pyrid-2-ylmethyl)-ethylenediamine (L5) and N-methyl-N′-(pyridin-2-ylmethyl)benzene-1,2-diamine (L6), has been isolated and studied as functional models for catechol oxidase enzymes in different aqueous micellar media. The X-ray crystal structures of 2 and 5 contain a CuN3Cl2 chromophore with a trigonal bipyramidal based coordination geometry. Interestingly, all the complexes form cationic [Cu(L)(DBC)(H2O)]+ adduct species in which DBC2? acts as a monodentate ligand, and the adduct species interacts strongly with anionic SDS micelles. The rates of the oxygenase reaction follow the trend SDS > TX-100 ～ water > CTAB, revealing that the rate of the reaction in micellar media are higher than those in aqueous solution and that the nature of biomimetic microenvironments of the micellized copper(II) catalyst and also the ligand stereoelectronic factors like donor atom basicity and steric bulk of ligand N-alkyl substituents, determine the catecholase-like activity.
Synthesis of Imidazolinium Salts by Pd/C-Catalyzed Dehydrogenation of Imidazolidines
Ando, Shin,Ishizuka, Tadao,Xiao, Bowen
supporting information, p. 4551 - 4554 (2021/08/30)
A method for the synthesis of imidazolinium salts through a catalytic dehydrogenation was developed using Pd/C as a catalyst with ammonium salt as an additive. Optimization of the reaction conditions revealed the existence of a proton source that was necessary to accomplish the reaction. Under the optimal conditions, oxidation-sensitive components, such as an allyl, a furan, and a thiophene can be introduced into the corresponding imidazolinium salts. In addition to the varied N-substituents, the presented method can be used to synthesize a series of 2-substituted imidazolinium salts.
New pinene-derived pyridines as bidentate chiral ligands
Malkov, Andrei V.,Stewart-Liddon, Angus J.P.,Teply, Filip,Kobr, Luká?,Muir, Kenneth W.,Haigh, David,Ko?ovsky, Pavel
, p. 4011 - 4025 (2008/09/20)
A synthesis of new bidentate pyridines 8a-d, 9, and 10 has been developed, starting from triflate 14, readily available from β-pinene 11. A copper complex of the pyridine-oxazoline ligands 8a has been found to catalyze asymmetric allylic oxidation of cyclic olefins 36a-c with good conversion rates and acceptable enantioselectivity (≤67% ee). The imidazolium salt 10 has been identified as a precursor of the corresponding N,N′-unsymmetrical N-heterocyclic carbene ligand, whose complex with palladium catalyzed the intramolecular amide enolate α-arylation leading to oxindole 45 in excellent yield but with low enantioselectivity.
