1
|
Gurská M, Brezová V, Šalitroš I, Švorc Ľ, Špánik I, Moncoľ J, Pavlik J, Szolcsányi P. Polyradical PROXYL/TEMPO Conjugates Connected by Ester/Amide Bridges: Synthesis, Physicochemical Studies, and DFT Calculations. Chempluschem 2021; 86:396-405. [PMID: 33645915 DOI: 10.1002/cplu.202000803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 02/11/2021] [Indexed: 12/16/2022]
Abstract
A series of di-/trinitroxide esters and amides featuring PROXYL and/or TEMPO radicals connected with alicyclic bridges were prepared in 61-92 % yields and their properties were analysed by using multiple experimental techniques. The examination of EPR spectra of radicals in organic solvents augmented with DFT calculations brought valuable information on the conformational dynamics and spin exchange mechanisms. Cyclic voltammetry investigations revealed (quasi)reversible electrochemical behaviour of studied nitroxides with their half-wave potentials ranging from -51 to -17 mV. SQUID measurements of selected radicals revealed that the magnetism of di- and trinitroxides is significantly different, since antiferromagnetic coupling in biradicals is notably larger than in triradicals. The single-crystal X-ray analysis of selected biradicals revealed the existence of 3D supramolecular networks of molecules linked through hydrogen-bonding interactions. These polynitroxide radicals can serve as promising bridging or chelating ligands in the synthesis of transition-metal-based molecular magnets.
Collapse
Affiliation(s)
- Mária Gurská
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovak Republic.,Polymer Institute, Slovak Academy of Sciences, Dúbravská cesta 9, SK-845 41, Bratislava, Slovak Republic
| | - Vlasta Brezová
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovak Republic
| | - Ivan Šalitroš
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovak Republic.,Department of Inorganic Chemistry, Faculty of Science, Palacký University, 17. listopadu 12, 771 46, Olomouc, Czech Republic.,Central European Institute of Technology, Brno University of Technology, Purkyňova 123, 61200, Brno, Czech Republic
| | - Ľubomír Švorc
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovak Republic.,Department of Chemistry, Faculty of Natural Sciences, Matej Bel University, Tajovského 40, SK-974 00, Banská Bystrica, Slovak Republic
| | - Ivan Špánik
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovak Republic
| | - Ján Moncoľ
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovak Republic
| | - Ján Pavlik
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovak Republic
| | - Peter Szolcsányi
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovak Republic
| |
Collapse
|
2
|
Lambert KM, Stempel ZD, Kiendzior SM, Bartelson AL, Bailey WF. Enhancement of the Oxidizing Power of an Oxoammonium Salt by Electronic Modification of a Distal Group. J Org Chem 2018; 82:11440-11446. [PMID: 28968489 DOI: 10.1021/acs.joc.7b01965] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The multigram preparation and characterization of a novel TEMPO-based oxoammonium salt, 2,2,6,6-tetramethyl-4-(2,2,2-trifluoroacetamido)-1-oxopiperidinium tetrafluoroborate (5), and its corresponding nitroxide (4) are reported. The solubility profile of 5 in solvents commonly used for alcohol oxidations differs substantially from that of Bobbitt's salt, 4-acetamido-2,2,6,6-tetramethyl-1-oxopiperidinium tetrafluoroborate (1). The rates of oxidation of a representative series of primary, secondary, and benzylic alcohols by 1 and 5 in acetonitrile solvent at room temperature have been determined, and oxoammonium salt 5 has been found to oxidize alcohols more rapidly than does 1. The rate of oxidation of meta- and para-substituted benzylic alcohols by either 1 or 5 displays a strong linear correlation to Hammett parameters (r > 0.99) with slopes (ρ) of -2.7 and -2.8, respectively, indicating that the rate-limiting step in the oxidations involves hydride abstraction from the carbinol carbon of the alcohol substrate.
Collapse
Affiliation(s)
- Kyle M Lambert
- Department of Chemistry, University of Connecticut , Storrs, Connecticut 06269-3060, United States
| | - Zachary D Stempel
- Department of Chemistry, University of Connecticut , Storrs, Connecticut 06269-3060, United States
| | - Sadie M Kiendzior
- Department of Chemistry, University of Saint Joseph , West Hartford, Connecticut 06117-2791, United States
| | - Ashley L Bartelson
- Department of Chemistry, Seton Hill University , Greensburg, Pennsylvania 15601, United States
| | - William F Bailey
- Department of Chemistry, University of Connecticut , Storrs, Connecticut 06269-3060, United States
| |
Collapse
|
3
|
Poprac P, Poliak P, Kavala M, Barbieriková Z, Zalibera M, Fronc M, Švorc Ľ, Vihonská Z, Olejníková P, Lušpai K, Lukeš V, Brezová V, Szolcsányi P. Polyradical PROXYL/TEMPO-Derived Amides: Synthesis, Physicochemical Studies, DFT Calculations, and Antimicrobial Activity. Chempluschem 2017; 82:1326-1340. [PMID: 31957189 DOI: 10.1002/cplu.201700343] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 10/18/2017] [Indexed: 01/09/2023]
Abstract
A series of polynitroxide amides possessing 2,2,5,5-tetramethyl-1-pyrrolidinyloxy (PROXYL) and/or 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) units connected through various bridges were synthesized and their properties were analyzed. EPR spectroscopy provided detailed insight into their paramagnetic character and related properties. A thorough examination of the EPR spectra of dinitroxides in organic solvents provided valuable information on the intramolecular motions, thermodynamics, and spin-exchange mechanisms. Analysis of low-temperature X- and Q-band EPR spectra of the dissolved dinitroxides provided spin-spin distances that were comparable with the theoretical values obtained by DFT. Cyclic voltammetry investigations revealed (quasi)reversible electrochemical behavior for PROXYL-derived biradicals, whereas significant loss of the reversibility was found for TEMPO-containing bi- and polyradicals. The inhibitory activities of the nitroxides against model bacteria, yeasts, and filamentous fungi were assessed.
Collapse
Affiliation(s)
- Patrik Poprac
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovakia
| | - Peter Poliak
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovakia
| | - Miroslav Kavala
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovakia
| | - Zuzana Barbieriková
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovakia
| | - Michal Zalibera
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovakia
| | - Marek Fronc
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovakia
| | - Ľubomír Švorc
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovakia
| | - Zuzana Vihonská
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovakia
| | - Petra Olejníková
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovakia
| | - Karol Lušpai
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovakia
| | - Vladimír Lukeš
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovakia
| | - Vlasta Brezová
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovakia
| | - Peter Szolcsányi
- Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK-812 37, Bratislava, Slovakia
| |
Collapse
|
4
|
Ionita G, Madalan AM, Ariciu AM, Medvedovici A, Ionita P. Synthesis of novel TEMPO stable free (poly)radical derivatives and their host–guest interaction with cucurbit[6]uril. NEW J CHEM 2016. [DOI: 10.1039/c5nj01518a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The line shape analysis of the ESR spectra of TEMPO derivatives in the absence and in the presence of cucurbit[6]uril provides information on host–guest complexes.
Collapse
Affiliation(s)
- Gabriela Ionita
- “Ilie Murgulescu” Institute of Physical Chemistry of the Romanian Academy
- Bucharest
- Romania
| | - Augustin M. Madalan
- Inorganic Chemistry Department
- Faculty of Chemistry
- University of Bucharest
- 020464-Bucharest
- Romania
| | - Ana Maria Ariciu
- “Ilie Murgulescu” Institute of Physical Chemistry of the Romanian Academy
- Bucharest
- Romania
- Department of Organic Chemistry
- Biochemistry and Catalysis
| | - Andrei Medvedovici
- Department of Analytical Chemistry
- University of Bucharest
- Bucharest
- Romania
| | - Petre Ionita
- “Ilie Murgulescu” Institute of Physical Chemistry of the Romanian Academy
- Bucharest
- Romania
- Department of Organic Chemistry
- Biochemistry and Catalysis
| |
Collapse
|
5
|
Krisiloff DB, Krauter CM, Ricci FJ, Carter EA. Density Fitting and Cholesky Decomposition of the Two-Electron Integrals in Local Multireference Configuration Interaction Theory. J Chem Theory Comput 2015; 11:5242-51. [DOI: 10.1021/acs.jctc.5b00762] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- David B. Krisiloff
- Departments of †Chemistry and ‡Mechanical and
Aerospace Engineering, ∥Program in Applied
and Computational Mathematics, and ¶Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544, United States
| | - Caroline M. Krauter
- Departments of †Chemistry and ‡Mechanical and
Aerospace Engineering, ∥Program in Applied
and Computational Mathematics, and ¶Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544, United States
| | - Francis J. Ricci
- Departments of †Chemistry and ‡Mechanical and
Aerospace Engineering, ∥Program in Applied
and Computational Mathematics, and ¶Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544, United States
| | - Emily A. Carter
- Departments of †Chemistry and ‡Mechanical and
Aerospace Engineering, ∥Program in Applied
and Computational Mathematics, and ¶Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544, United States
| |
Collapse
|
6
|
Romano F, Manoni R, Franchi P, Mezzina E, Lucarini M. Supramolecular control of spin exchange in a spin-labelled [2]rotaxane incorporating a tetrathiafulvalene unit. Chemistry 2015; 21:2775-9. [PMID: 25538046 DOI: 10.1002/chem.201406301] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Indexed: 11/07/2022]
Abstract
The EPR properties of a novel triradical obtained by single-electron oxidation of a nitroxide-spin-labelled rotaxane containing a tetrathiafulvalene unit and cyclobis(paraquat-p-phenylene) ring is reported. Rotaxanation is proved to have a dramatic effect on through-space magnetic interactions between radical fragments. Analysis of the EPR spectra by a three-jump model, allowed us to obtain structural information on the interlocked structure.
Collapse
Affiliation(s)
- Francesco Romano
- Department of Chemistry "G. Ciamician", University of Bologna, Via S. Giacomo 11, 40126, Bologna (Italy) http://www.ciam.unibo.it/radicals
| | | | | | | | | |
Collapse
|