Cu-tethered macrocycle catalysts: Synthesis and size-selective CO2-fixation to propargylamines under ambient conditions
摘要:
A novel air-stable, Cu-tethered macrocycle catalyst possessing a large inner cavity was successfully synthesized, creating a unique supramolecular catalytic system. The catalyst was utilized in the CO2-fixation reaction to propargylamines. The reaction proceeded more efficiently compared to the conventional CuI catalyst under atmospheric CO2 condition. Notably, owing to its topological effect, the Cu-tethered macrocycle catalyst exhibited unique substrate size selectivity. (C) 2020 Elsevier Ltd. All rights reserved.
Cu-tethered macrocycle catalysts: Synthesis and size-selective CO2-fixation to propargylamines under ambient conditions
摘要:
A novel air-stable, Cu-tethered macrocycle catalyst possessing a large inner cavity was successfully synthesized, creating a unique supramolecular catalytic system. The catalyst was utilized in the CO2-fixation reaction to propargylamines. The reaction proceeded more efficiently compared to the conventional CuI catalyst under atmospheric CO2 condition. Notably, owing to its topological effect, the Cu-tethered macrocycle catalyst exhibited unique substrate size selectivity. (C) 2020 Elsevier Ltd. All rights reserved.
A [3]rotaxane consisting of two 30-membered rings threaded by a symmetrical filament-like fragment was synthesized thanks to the copper(I)-template effect. The filament incorporates two tridentate coordinating units and two bidentate chelating groups. In addition to the [3]rotaxane, two homologous compounds were isolated in very significant yields: the corresponding [2]- and [4]-rotaxanes containing
Use of Cleavable Coordinating Rings as Protective Groups in the Synthesis of a Rotaxane with an Axis that Incorporates More Chelating Groups Than Threaded Macrocycles
methodology allowing preparation of a linear “unsaturated” [3]rotaxane consisting of an axis incorporating more coordination sites than threaded rings was developed. It was based on the preliminary synthesis of a “saturated” [5]rotaxane consisting of a four‐chelating site axis threaded through four macrocyclic components, two of them being cleavable rings incorporating a lactone function and the two
New [3]rotaxanes and [3]pseudorotaxanes have been synthesised using the “gathering and threading” effect of copper(I). By using click chemistry as the “stoppering” reaction, a good yield of the [3]rotaxane was obtained, either as a dicopper complex or as a metal-free compound after demetallation. The axle contains a central rigid aromatic block incorporating two bidentate chelates, and the threaded macrocycles are 30-membered rings. A model dicopper(I) [3]pseudorotaxane whose axle was end-functionalised by triisopropylsilyl groups could be crystallised and studied by X-ray diffraction. A particularly attractive structure was obtained showing a “slanted” geometry for the two rings and the axle, the two 1,10-phenanthroline units of the rings being almost parallel to one another but their respective mean planes being more than 7 Å apart.
processes is the lowest singlet state of the DCNQ moiety (S1), which exhibits strong charge‐transfer character and a lifetime of 0.4 ps. Its deactivation leads to population of another excitedstate with a lifetime of 1.3 ps, which can be the related triplet state (T1) or a vibrationally hot level (hot‐S0). Notably, S1 also shows stimulated fluorescence in the near‐infrared (NIR) region between 1100
Quantitative Formation of [2]Catenanes Using Copper(I) and Palladium(II) as Templating and Assembling Centers: The Entwining Route and the Threading Approach
type of coordination catenanes incorporating Cu(I) and Pd(II) metal centers. The ligand designed here contains a phenanthroline core and pyridine sidearms (compound 1). Using this phenanthroline-pyridine conjugated ligand, two approaches were examined, which were shown to be surprisingly efficient for the catenane synthesis: the entwining route (entwining of two ligands around Cu(I) followed by Pd(II)