140174-48-7Relevant articles and documents
TIMPZ: An Exquisite Building Block for Metal/Hydrogen Coordination Polymers
Ligiéro, Carolina B. P.,Oliveira, Thiago V.,Fontes, Chárbel C. F.,Barragan, José T. C.,So, Fernanda W. Y.,Kubota, Lauro T.,Nome, René A.,Miranda, Paulo C. M. L.
, p. 2291 - 2294 (2019)
The novel polynitrogenated ligand tetra-[4(5)-imidazoyl]pyrazine (TIMPZ, 1) and its pincer complex of FeII are described. This ligand has an outstanding ability to aggregate in 1D-superstructures by means of hydrogen bonding or metal chelation. TIMPZ shows an unprecedented conformational control over the supramolecular assembly. Metal or hydrogen coordination switches the conformation of peripheral rings driving the assembly preferences. For [Fen(TIMPZ)n+1]2n+ complexes, UV/Vis spectroscopy shows a bathochromic shift of the main visible absorption band with higher “n” values. TIMPZ also has hydrogen-bond triggered excited-state intramolecular proton transfer (ESIPT) fluorescence, which is completely inhibited by chelation with transition metals.
Studies toward the total synthesis of nagelamide K
Jiang, Biao,Wang, Jue,Huang, Zuo-Gang
, p. 2070 - 2073 (2012)
A stereocontrolled strategy toward the synthesis of nagelamide K has been developed. The dimeric imidazole acrylate, diimidazolidenesuccinate, was constructed as a synthetic precursor by a Ni-catalyzed coupling reaction; the microwave-promoted intramolecular aza-Michael addition afforded the imidazo[1,5-a]pyridine core structure of nagelamide K in high stereoselectivity. A detaurine-dediamino analogue of nagelamide K has been prepared.
Functionalization of the Imidazole Backbone by Means of a Tailored and Optimized Oxidative Heck Cross-Coupling
Cirillo, Davide,Angelucci, Francesco,Bj?rsvik, Hans-René
, p. 5079 - 5092 (2020/09/23)
A general and selective Pd-catalyzed cross-coupling of aromatic boronic acids with vinyl-imidazoles is disclosed. Unlike most cross-coupling reactions, this method operates well in absence of bases avoiding the formation of by-products. The reactivity is highly enhanced by the presence of nitrogen-based ligands, in particular bathocuproine. The method involves MnO2 as oxidant for the oxidation Pd (0)→Pd (II), a much weaker oxidant than previously reported in the literature. This allows for the use of reactants that possess a multitude of functional groups. A scope and limitation study involving a series of 24 boronic acids, whereof 18 afforded TMs in yields in the range 41–95%. The disclosed method constitutes the first general method for the oxidative Heck cross-coupling on the imidazole scaffold, which moreover operates with a selection of other heterocycles. (Figure presented.).