89333-97-1Relevant articles and documents
Cu-tethered macrocycle catalysts: Synthesis and size-selective CO2-fixation to propargylamines under ambient conditions
Kim, Nam-Kyun,Sogawa, Hiromitsu,Takata, Toshikazu
, (2020/05/01)
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.
Isolating substituent effects in Re(I)-phenanthroline electrocatalysts for CO2 reduction
Roell, Sarah A.,Schrage, Briana R.,Ziegler, Christopher J.,White, Travis A.
, (2020/01/02)
The development of highly-active molecular electrocatalysts for reducing CO2 to value-added products requires an intimate knowledge of the structural and electronic features surrounding the active site. We previously illustrated how electronic modifications to fac-[ReI(R2phen)(CO)3Cl] electrocatalysts (R2phen = 2,9-disubstituted-1,10-phenanthrolines) strongly dictate CO2 reduction; more specifically, introducing methoxy substituents at both the ortho/para positions of a phenyl ring attached to phenanthroline generated high catalytic activity. In the current work, we have prepared four structurally-related Re(I) electrocatalysts to isolate the electronic effects associated with each methoxy group's positioning around the phenyl ring (i.e. none, ortho, meta, or para). The diimine ligands 2,9-diphenyl-1,10-phenanthroline (Ph2phen), 2,9-bis(2,6-dimethoxyphenyl)-1,10-phenanthroline ((2,6-dmp)2phen), 2,9-bis(3,5-dimethoxyphenyl)-1,10-phenanthroline ((3,5-dmp)2phen), and 2,9-bis(4-methoxyphenyl)-1,10-phenanthroline ((4-mp)2phen) were prepared, and the subsequent fac-[ReI(R2phen)(CO)3Cl] complexes were synthesized, characterized, and studied for electrocatalytic CO2 reduction. Following 90 min electrolysis at Eapp = ?2.55 V vs. Fc+/0 in DMF solvent, the ortho methoxy-substituted analogue (labeled Re((2,6-dmp)2phen)) produced 35 μmol CO, corresponding to a turnover number = 14 (TON = mol CO per mol Re catalyst) and a Faradaic efficiency = 84% (F.E. = mol CO per mol electrons). The remaining Re electrocatalysts produced significantly lower levels of CO (Re(Ph2phen): 1.8 μmol CO; Re((3,5-dmp)2phen): 2.4 μmol; Re((4-mp)2phen): 4.2 μmol CO), emphasizing the important electronic contribution that ortho substituted methoxy groups provide towards enhancing electron density at the Re active site to rapidly, and selectively, convert CO2 substrate to CO product.
One-Pot Synthesis of a Linear [4]Catenate Using Orthogonal Metal Templation and Ring-Closing Metathesis
Amir, Faheem,Barnes, Jonathan C.,Chang, Christy,Colley, Nathan D.,Fisher, Jeremy M.,Greene, Angelique F.,Li, Lei,Li, Ruihan,Li, Xuesong,Nosiglia, Mark A.
supporting information, (2020/08/12)
The efficient synthesis of well-defined, linear oligocatenanes possessing multiple mechanical bonds remains a formidable challenge in the field of mechanically interlocked molecules. Here, a one-pot synthetic strategy is described to prepare a linear [4]catenate using orthogonal metal templation between a macrocycle precursor, composed of terpyridine and phenanthroline ligands spaced by flexible glycol linkers, and a closed phenanthroline-based molecular ring. Implementation of two simultaneous ring-closing metathesis reactions after metal complexation resulted in the formation of three mechanical bonds. The linear [4]catenate product was isolated in 55% yield as a mixture of topological diastereomers. The intermediate metal complexes and corresponding interlocked products (with and without metals) were characterized by nuclear magnetic resonance, mass spectrometry, gel permeation chromatography, and UV-vis absorption spectroscopy. We envision that this general synthetic strategy may pave the way for the synthesis of higher order linear oligocatenates/catenanes with precise molecular weights and four or more interlocking molecular rings.
Characterization and photocatalytic behavior of 2,9-di(aryl)-1,10-phenanthroline copper(i) complexes
Cetin, M. Mustafa,Hodson, Roman T.,Hart, C. Robin,Cordes, David B.,Findlater, Michael,Casadonte, Dominick J.,Cozzolino, Anthony F.,Mayer, Michael F.
, p. 6553 - 6569 (2017/07/11)
The synthesis, characterization, photophysical properties, theoretical calculations, and catalytic applications of 2,9-di(aryl)-1,10-phenanthroline copper(i) complexes are described. Specifically, this study made use of di(aryl)-1,10-phenanthroline ligands including 2,9-di(4-methoxyphenyl)-1,10-phenanthroline (1), 2,9-di(4-hydroxyphenyl)-1,10-phenanthroline (2), 2,9-di(4-methoxy-3-methylphenyl)-1,10-phenanthroline (3), and 2,9-di(4-hydroxy-3-methylphenyl)-1,10-phenanthroline (4). The 2:1 ligand-to-metal complexes, as PF6- salts, i.e., ([Cu·(1)2]PF6, [Cu·(2)2]PF6, [Cu·(3)2]PF6, and [Cu·(4)2]PF6) have been isolated and characterized. The structures of ligands 1 and 2 and complexes [Cu·(1)2]PF6 and [Cu·(3)2]PF6 have been determined by single-crystal X-ray analysis. The photoredox catalytic activity of these copper(i) complexes was investigated in an atom-transfer radical-addition (ATRA) reaction and the results showed fairly efficient activity, with a strong wavelength dependence. In order to better understand the observed catalytic activity, photophysical emission and absorption studies, and DFT calculations were also performed. It was determined that when the excitation wavelength was appropriate for exciting into the LUMO+1 or LUMO+2, catalysis would occur. On the contrary, excitations into the LUMO resulted in no observable catalysis. In light of these results, a mechanism for the ATRA photoredox catalytic cycle has been proposed.
Supramolecular polymerization of a ureidopyrimidinone-based [2]catenane prepared via ring-closing metathesis
Teunissen, Abraham J. P.,Berrocal, José Augusto,Corbet, Christiaan H. W. A.,Meijer
, p. 2971 - 2976 (2017/08/08)
The synthesis of a Sauvage-type [2]catenane featuring a quadruple hydrogen bonding ureidopyrimidinone (UPy) motif in each ring was reported. Intermolecular dimerization of the UPy motifs induces the hydrogen-bond-driven supramolecular polymerization of the [2]catenane monomer, thereby creating a linear polymer consisting of both hydrogen bonding and mechanical bonds. As the rings in the UPy catenane are asymmetric, two stereoisomers can be formed upon catenation, that is, with the phenanthroline moieties oriented +90° or -90° with respect to each other. Based on the phenanthroline-Cu(I) and ring-closing metathesis (RCM) approach, we first devised a synthetic procedure for the synthesis of the UPy-based catenane. Here, phenanthroline was first functionalized with phenol moieties in a two-step approach with an overall yield of 46%. The resulting biphenol 3 was then alkylated in a statistical manner with a mixture of 4-bromobut-1-ene and t-Boc-protected bromide resulting in t-Boc-protected compound. The results show that protection of the UPy motifs is necessary for this reaction to reach completion. Analysis of the unprotected UPy catenane by 1H NMR revealed the formation of UPy-UPy dimers and significant broadening of the signals, both in presence and absence of Cu(I).
The role of organic linkers in directing DNA self-assembly and significantly stabilizing DNA duplexes
Greschner, Andrea A.,Toader, Violeta,Sleiman, Hanadi F.
supporting information, p. 14382 - 14389 (2012/10/29)
We show a simple method to control both the stability and the self-assembly behavior of DNA structures. By connecting two adjacent duplexes with small synthetic linkers, factors such as linker rigidity and DNA strand orientation can increase the thermal denaturation temperature of 17 base-pair duplexes by up to 10 °C, and significantly increase the cooperativity of melting of the two duplexes. The same DNA sequence can thus be tuned to melt at vastly different temperatures by selecting the linker structure and DNA-to-linker connectivity. In addition, a small rigid m-triphenylene linker directly affects the self-assembly product distribution. With this linker, changes in the orientation of the linked strands (e.g., 5′3′ vs 3′3′) can lead to dramatic changes in the self-assembly behavior, from the formation of cyclic dimer and tetramer to higher-order oligomers. These variations can be readily predicted using a simple strand-end alignment model.
[Cu(dap)2Cl] as an efficient visible-light-driven photoredox catalyst in carbon-carbon bond-forming reactions
Pirtsch, Michael,Paria, Suva,Matsuno, Taisuke,Isobe, Hiroyuki,Reiser, Oliver
supporting information; experimental part, p. 7336 - 7340 (2012/09/08)
Copper sees the light of day: [Cu(dap)2Cl] proved to be an excellent photoredox catalyst for atom-transfer radical addition reactions, as well as for allylation reactions (see scheme), providing an attractive alternative to commonly used iridium- and ruthenium-based catalysts. Copyright
Polymer catenanes via a supramolecularly templated ATRP initiator
Bunha, Ajaykumar,Tria, Maria Celeste,Advincula, Rigoberto
supporting information; experimental part, p. 9173 - 9175 (2011/11/29)
Synthesis of polymer catenanes via a living radical polymerization and supramolecular template approach are demonstrated. The ring closure was performed via atom transfer radical cross coupling (ATRC) to obtain polymer catenanes from the linear polymer metal complex precursor.
Templated synthesis of highly stable, electroactive, and dynamic metal-DNA branched junctions
Yang, Hua,Sleiman, Hanadi F.
, p. 2443 - 2446 (2008/12/23)
(Figure Presented) Templated metalation of DNA junctions allows incorporation of a range of transition metals into DNA assemblies. The resulting highly stable metal-DNA junctions can be assembled into dynamic multinuclear structures, with metal centers as their corners and DNA single strands as their sides. Ready and reversible structural switching of these assemblies with external agents (see picture) allows for control of geometry and metal-metal distances.
An efficient chloride-selective fluorescent chemosensor based on 2,9-bis(4′-hydroxyphenyl)phenanthroline Cu(II) complex
Wu, Jia-Sheng,Wang, Peng-Fei,Zhang, Xiao-Hong,Wu, Shi-Kang
, p. 281 - 286 (2008/02/07)
A new complex Cu(II)/L, composed of 2,9-bis(4′-hydroxyphenyl)phenanthroline (L) and Cu(II), was synthesized as an efficient chloride-detection fluorescent chemosensor with high selectivity and sensitivity over other halide anions, F-, Br-, I-. The recognition mechanism was discussed primarily.
