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Belyakov AV, Kuznetsov VV, Shimanskaya GS, Rykov AN, Goloveshkin AS, Novakovskaya YV, Shishkov IF. Molecular structure of 1,1',6,6'-tetraaza-7,7'-bi(bicyclo[4.1.0]heptane) in gas, solid and solution phases: GED, XRD and NMR data combined with quantum chemical calculations. MENDELEEV COMMUNICATIONS 2023. [DOI: 10.1016/j.mencom.2023.01.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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2
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Kuznetsov V, Khakimov D, Dmitrenok A, Goloveshkin A. Synthesis, structure and peculiarity of conformational behavior of 1,5-diazabicyclo[3.1.0]hexanes. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.133856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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3
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Marochkin II, Altova EP, Kuznetsov VV, Rykov AN, Shishkov IF. Molecular structure of 6-cyclopropyl-1,5-diazabicyclo[3.1.0]hexane: gas phase electron diffraction and theoretical study. MENDELEEV COMMUNICATIONS 2022. [DOI: 10.1016/j.mencom.2022.07.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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4
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Betzenbichler G, Huber L, Kräh S, Morkos MLK, Siegle AF, Trapp O. Chiral stationary phases and applications in gas chromatography. Chirality 2022; 34:732-759. [PMID: 35315953 DOI: 10.1002/chir.23427] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 02/06/2022] [Accepted: 02/07/2022] [Indexed: 12/15/2022]
Abstract
Chiral compounds are ubiquitous in nature and play a pivotal role in biochemical processes, in chiroptical materials and applications, and as chiral drugs. The analysis and determination of the enantiomeric ratio (er) of chiral compounds is of enormous scientific, industrial, and economic importance. Chiral separation techniques and methods have become indispensable tools to separate chiral compounds into their enantiomers on an analytical as well on a preparative level to obtain enantiopure compounds. Chiral gas chromatography and high-performance liquid chromatography have paved the way and fostered several research areas, that is, asymmetric synthesis and catalysis in organic, medicinal, pharmaceutical, and supramolecular chemistry. The development of highly enantioselective chiral stationary phases was essential. In particular, the elucidation and understanding of the underlying enantioselective supramolecular separation mechanisms led to the design of new chiral stationary phases. This review article focuses on the development of chiral stationary phases for gas chromatography. The fundamental mechanisms of the recognition and separation of enantiomers and the selectors and chiral stationary phases used in chiral gas chromatography are presented. An overview over syntheses and applications of these chiral stationary phases is presented as a practical guidance for enantioselective separation of chiral compound classes and substances by gas chromatography.
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Affiliation(s)
| | - Laura Huber
- Department of Chemistry, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Sabrina Kräh
- Department of Chemistry, Ludwig-Maximilians-University Munich, Munich, Germany
| | | | - Alexander F Siegle
- Department of Chemistry, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Oliver Trapp
- Department of Chemistry, Ludwig-Maximilians-University Munich, Munich, Germany
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5
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Kolesnikova IN, Kuznetsov VV, Goloveshkin AS, Chegodaev NA, Makhova NN, Shishkov IF. 6,6′-Dimethyl-1,1′,5,5′-tetraaza-6,6′-bi(bicyclo[3.1.0]hexane): synthesis and investigation of molecular structure by quantum-chemical calculations, NMR spectroscopy and X-ray diffraction analysis. Struct Chem 2021. [DOI: 10.1007/s11224-021-01806-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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6
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Ageev GG, Rykov AN, Grikina OE, Shishkov IF, Kochikov IV, Kuznetsov VV, Makhova NN, Bukalov SS. Equilibrium Molecular Structure of 3,3,6-trimethyl-1,5-diazabicyclo[3.1.0]hexane: the joint analysis of the gas-phase electron diffraction data and quantum chemical simulations. Struct Chem 2021. [DOI: 10.1007/s11224-021-01828-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Tachrim ZP, Wang L, Murai Y, Hashimoto M. New Trends in Diaziridine Formation and Transformation (a Review). Molecules 2021; 26:4496. [PMID: 34361648 PMCID: PMC8348119 DOI: 10.3390/molecules26154496] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 07/19/2021] [Accepted: 07/20/2021] [Indexed: 01/18/2023] Open
Abstract
This review focuses on diaziridine, a high strained three-membered heterocycle with two nitrogen atoms that plays an important role as one of the most important precursors of diazirine photoaffinity probes, as well as their formation and transformation. Recent research trends can be grouped into three categories, based on whether they have examined non-substituted, N-monosubstituted, or N,N-disubstituted diaziridines. The discussion expands on the conventional methods for recent applications, the current spread of studies, and the unconventional synthesis approaches arising over the last decade of publications.
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Affiliation(s)
- Zetryana Puteri Tachrim
- Division of Applied Bioscience, Graduate School of Agriculture, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo 060-8589, Japan; (L.W.); (Y.M.)
- Research Center for Chemistry, Indonesian Institute of Sciences, Kawasan Puspiptek, Serpong, South Tangerang 15314, Banten, Indonesia
| | - Lei Wang
- Division of Applied Bioscience, Graduate School of Agriculture, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo 060-8589, Japan; (L.W.); (Y.M.)
- State Key Laboratory of Fine Chemicals, Department of Pharmacy, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China
| | - Yuta Murai
- Division of Applied Bioscience, Graduate School of Agriculture, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo 060-8589, Japan; (L.W.); (Y.M.)
- Frontier Research Center for Post-Genome Science and Technology, Faculty of Advanced Life Science, Hokkaido University, Kita 21, Nishi 11, Kita-ku, Sapporo 001-0021, Japan
| | - Makoto Hashimoto
- Division of Applied Bioscience, Graduate School of Agriculture, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo 060-8589, Japan; (L.W.); (Y.M.)
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8
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Khakimov DV, Fershtat LL, Pivina TS, Makhova NN. Nitrodiaziridines: Unattainable yet, but Desired Energetic Materials. J Phys Chem A 2021; 125:3920-3927. [PMID: 33909974 DOI: 10.1021/acs.jpca.1c02960] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Using quantum chemical methods and the original technique based on atom-atom potential methods, the molecular and crystal structure simulation of all possible structural forms of nitrodiaziridines were carried out. The possible pathways of thermal decomposition of nitrodiaziridines were modeled, and the most stable forms were identified. Thermodynamic stability, physicochemical characteristics, and detonation properties were also estimated. The obtained results enable a huge potential of the nitrodiaziridine-based compounds as high-energy materials for a variety of applications.
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Affiliation(s)
- Dmitry V Khakimov
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47 Leninsky prosp., Moscow 119991, Russian Federation.,Federal State Unitary Enterprise "Keldysh Research Center", Onezhskaya Str., 8, Moscow 125438, Russian Federation
| | - Leonid L Fershtat
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47 Leninsky prosp., Moscow 119991, Russian Federation
| | - Tatyana S Pivina
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47 Leninsky prosp., Moscow 119991, Russian Federation
| | - Nina N Makhova
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47 Leninsky prosp., Moscow 119991, Russian Federation
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Ravindra S, Irfana Jesin CP, Shabashini A, Nandi GC. Recent Advances in the Preparations and Synthetic Applications of Oxaziridines and Diaziridines. Adv Synth Catal 2021. [DOI: 10.1002/adsc.202001372] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Sundaresan Ravindra
- Department of Chemistry National Institute of Technology Tiruchirappalli 620015, Tamilnadu India
| | - C. P. Irfana Jesin
- Department of Chemistry National Institute of Technology Tiruchirappalli 620015, Tamilnadu India
| | - Arivalagan Shabashini
- Department of Chemistry National Institute of Technology Tiruchirappalli 620015, Tamilnadu India
| | - Ganesh Chandra Nandi
- Department of Chemistry National Institute of Technology Tiruchirappalli 620015, Tamilnadu India
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Molecular structure of 1,2-diethyldiaziridine studied by gas electron diffraction supported by quantum chemistry calculations. J Mol Struct 2021. [DOI: 10.1016/j.molstruc.2020.129066] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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11
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Khaikin LS, Ageev GG, Grikina OE, Shishkov IF, Kuznetsov VV, Makhova NN. Intramolecular Motions in 1,2,3-Triethyldiaziridine: A Quantum Chemistry Study. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2020. [DOI: 10.1134/s0036024420090125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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12
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Makhova NN, Belen’kii LI, Gazieva GA, Dalinger IL, Konstantinova LS, Kuznetsov VV, Kravchenko AN, Krayushkin MM, Rakitin OA, Starosotnikov AM, Fershtat LL, Shevelev SA, Shirinian VZ, Yarovenko VN. Progress in the chemistry of nitrogen-, oxygen- and sulfur-containing heterocyclic systems. RUSSIAN CHEMICAL REVIEWS 2020. [DOI: 10.1070/rcr4914] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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13
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Khaikin LS, Ageev GG, Rykov AN, Grikina OE, Shishkov IF, Kochikov IV, Kuznetsov VV, Makhova NN, Bukalov SS, Leites LA. Equilibrium molecular structure and spectra of 6-methyl-1,5-diazabicyclo[3.1.0]hexane: joint analysis of gas phase electron diffraction, quantum chemistry, and spectroscopic data. Phys Chem Chem Phys 2020; 22:22477-22492. [PMID: 32996973 DOI: 10.1039/d0cp04005c] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The equilibrium geometry of the boat conformation (Cs point group symmetry) of the 6-methyl-1,5-diazabicyclo[3.1.0]hexane (MDABH) molecule, absolutely dominating under normal conditions, was studied by the gas-phase electron diffraction (GED) method at 20 °C with the involvement of NMR, IR, and Raman spectroscopic data and quantum chemical calculations. The potential function of ring-puckering deformation for the MDABH bicyclic system was calculated at the MP2/aug-cc-pVTZ and B3LYP/cc-pVTZ levels. It was found by MP2 calculation that the total energy of the boat conformation is 3.52 kcal mol-1 lower than that of the chair conformation. For the first time, we recorded the IR and Raman spectra for liquid samples of MDABH and assigned their peculiarities only to boat conformation vibrations using the Pulay technique of scaling quantum chemical force fields. In the case of the chair form, transferability of the refined scale factors was used for reliable prediction of the location of its fundamental frequencies. According to the joint structural analysis of the above data, the most important equilibrium geometric re-parameters for the boat conformation of the MDABH molecule were determined to be (bond lengths in Å; angles in degrees, Cs symmetry): C2N1 = 1.466(2), C2C3 = 1.523(2), N1N5 = 1.512(2), C6N1 = 1.440(2), C6C7 = 1.487(2), ∠C2N1N5 = 106.1(2), ∠N1C2C3) = 110.2(4), ∠C2C3C4 = 99.9(4), ∠N1N5C6 = 58.3(1), ∠N1C6N5 = 63.3(1), ∠N1C6C7 = 114.9(6), ∠C6N1C2 = 111.8(1), ∠N5N1C2C3 = 17.3(1), ∠N1C2C3C4 = -26.8(2), θ = C2C3C4/C2N1N5C4 = -26.2(3), φ = N1C6N5/C2N1N5C4 = 74.0(1). Comparison of these and earlier results showed that the NN bond length in the diaziridine ring is very weakly dependent on the cis- or trans-arrangement of substituents at the nitrogen atoms.
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Affiliation(s)
- Leonid S Khaikin
- Chemistry Department, M. V. Lomonosov Moscow State University, 1 Leninsky Gory, 119991, Moscow, Russia.
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14
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Multidimensional gas chromatography investigation of concentration and temperature effects of oxime interconversion on ionic liquid and poly(ethylene glycol) stationary phases. Anal Chim Acta 2019; 1081:200-208. [DOI: 10.1016/j.aca.2019.07.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 07/01/2019] [Accepted: 07/07/2019] [Indexed: 01/22/2023]
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15
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Khaikin LS, Kochikov IV, Rykov AN, Grikina OE, Ageev GG, Shishkov IF, Kuznetsov VV, Makhova NN. Equilibrium structures of the tetramezine diastereomers and their ratio: joint analysis of gas phase electron diffraction, quantum chemistry, and spectroscopic data. Phys Chem Chem Phys 2019; 21:5598-5613. [PMID: 30785435 DOI: 10.1039/c8cp07607c] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
For the first time, we applied a gas-phase electron diffraction (GED) method together with vibrational spectroscopy and quantum chemical calculations to investigate the equilibrium geometries of achiral meso and enantiomeric diastereomers of tetramezine [1,2-bis-(3,3-dimethyldiaziridin-1-yl)ethane] and their ratio in the mixture. In the joint structural analysis of these data, a new approach based on PES parameters is used in the framework of a static molecular model (small amplitude motion approximation). The agreement between the theoretical and experimental molecular intensities is characterized by a divergence factor Rf of 5.9%. The experimental re-parameters of tetramezine diastereomers agreed with our B3LYP/cc-pVTZ and MP2/cc-pVTZ calculations, which predicted the total energy of the meso form (Ci point group symmetry) to be lower than that of the enantiomeric form (C2 point group symmetry), by 6.4 and 4.7 kJ mol-1, respectively. The experimentally measured percentages of the meso and both enantiomeric diastereoisomers at 360 K were 70% and 30%, respectively. We characterized the meso form using 2D NMR spectra. Our GED data are in good agreement with the X-ray diffraction analysis of the meso form. This result reflects the weak effect of intermolecular interactions in the crystal. We assigned the IR spectrum bands of the crystalline meso form using the Pulay technique of scaling quantum chemical force fields. In the case of the enantiomeric form calculated at the same level, transferability of the refined scale factors was used for more reliable prediction of the mutual location and interpretation of its fundamental frequencies.
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Affiliation(s)
- Leonid S Khaikin
- Chemistry Department, M. V. Lomonosov Moscow State University, 119991 Moscow, Russia.
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16
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Marochkin II, Kuznetsov VV, Rykov AN, Makhova NN, Shishkov IF. Molecular structure study of 1,2,3-trimethyldiaziridine by means of gas electron diffraction method. Struct Chem 2018. [DOI: 10.1007/s11224-018-1213-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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17
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Kuznetsov VV, Kachala VV, Makhova NN. Synthesis of hybrid structures comprising diaziridine and cyclopropane rings in one molecule. MENDELEEV COMMUNICATIONS 2018. [DOI: 10.1016/j.mencom.2018.09.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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18
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Mondal RR, Khamarui S, Maiti DK. Photocatalytic Generation of Nitrenes for Rapid Diaziridination. Org Lett 2018; 19:5964-5967. [PMID: 29056045 DOI: 10.1021/acs.orglett.7b02844] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A blue LED, an organic photocatalyst (rose bengal), and the Lewis acid like oxidant PhI(OAc)2 were utilized to generate nitrene intermediates through reactions of 1,2-diols and aliphatic amines under mild reaction conditions. A versatile and rapid diaziridination strategy was established to construct functionalized 1,2-disubstituted diaziridines, diaziridines with chiral substituents, and 1,2,3-trisubstituted analogues with excellent reaction rates, yields, and stereoselectivities. Control and labeling experiments to elucidate the mechanism of this elegant metal-free photocatalyzed cyclization reaction were performed.
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Affiliation(s)
- Ramij R Mondal
- Department of Chemistry, University of Calcutta, University College of Science , 92, A. P. C. Road, Kolkata 700009, India
| | - Saikat Khamarui
- Government General Degree College at Kalna-I , Muragacha, Medgachi, Burdwan 713405, India
| | - Dilip K Maiti
- Department of Chemistry, University of Calcutta, University College of Science , 92, A. P. C. Road, Kolkata 700009, India
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Diastereoselective synthesis of 1,3-di- and 1,3,3-trisubstituted diaziridines coupled with neurotransmitter amino acids. MENDELEEV COMMUNICATIONS 2016. [DOI: 10.1016/j.mencom.2016.09.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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20
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Zawatzky K, Kamuf M, Trapp O. Chiral 1,2-dialkenyl diaziridines: synthesis, enantioselective separation, and nitrogen inversion barriers. Chirality 2014; 27:156-62. [PMID: 25378198 DOI: 10.1002/chir.22405] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 10/12/2014] [Indexed: 11/09/2022]
Abstract
trans-1,2-Disubstituted diaziridines form stable enantiomers at ambient conditions because of the two stereogenic pyramidal nitrogen atoms. Functionalized trans-1,2-disubstituted diaziridines can be utilized as a chiral switching moiety between two enantiomeric states in more complex molecular structures. However, the synthesis of functionalized diaziridines is quite challenging, because of the limited tolerance of reaction conditions that can be applied. Here we present a strategy to make trans-1,2-disubstituted diaziridines accessible as versatile building blocks in C-C-bond formations, i.e., the Heck reaction, and therefore introducing aryl substituents. The synthesis of trans-1,2-dialkenyl diaziridines with terminal alkenyl substituents and their stereodynamic properties are described.
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Affiliation(s)
- Kerstin Zawatzky
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany
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Stockinger S, Gmeiner J, Zawatzky K, Troendlin J, Trapp O. From stereodynamics to high-throughput screening of catalysed reactions. Chem Commun (Camb) 2014; 50:14301-9. [DOI: 10.1039/c4cc04892j] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In this review we summarised recent developments in high-throughput kinetic monitoring of reactions including the dynamics of interconverting stereoisomers and the simultaneous combination of (catalysed) reactions with chemical analysis in on-column reaction chromatographic devices.
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Affiliation(s)
- Skrollan Stockinger
- Organisch-Chemisches Institut
- Ruprecht-Karls-Universität Heidelberg
- 69120 Heidelberg, Germany
| | - Julia Gmeiner
- Organisch-Chemisches Institut
- Ruprecht-Karls-Universität Heidelberg
- 69120 Heidelberg, Germany
| | - Kerstin Zawatzky
- Organisch-Chemisches Institut
- Ruprecht-Karls-Universität Heidelberg
- 69120 Heidelberg, Germany
| | - Johannes Troendlin
- Organisch-Chemisches Institut
- Ruprecht-Karls-Universität Heidelberg
- 69120 Heidelberg, Germany
| | - Oliver Trapp
- Organisch-Chemisches Institut
- Ruprecht-Karls-Universität Heidelberg
- 69120 Heidelberg, Germany
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Vanthuyne N, Roussel C. Chiroptical Detectors for the Study of Unusual Phenomena in Chiral Chromatography. Top Curr Chem (Cham) 2013; 340:107-51. [DOI: 10.1007/128_2013_441] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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23
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Kamuf M, Trapp O. Stereodynamics of small 1,2-dialkyldiaziridines. Chirality 2013; 25:224-9. [PMID: 23401088 DOI: 10.1002/chir.22131] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Accepted: 10/12/2012] [Indexed: 11/09/2022]
Abstract
Diaziridines are very interesting representatives of organic compounds containing stereogenic nitrogen atoms. In particular, 1,2-dialkyldiaziridines show extraordinarily high stereointegrity. The lone electron pairs of the nitrogen atoms are in trans configuration, avoiding a four-electron repulsive interaction. Furthermore, the trans configuration of the substituents at the nitrogen atoms is energetically favored because of reduced steric interactions. Therefore only two stereoisomers (enantiomers) are observed. At elevated temperatures the enantiomers are interconverting because of the limited stereointegrity of the chirotopic nitrogen atoms. The enantiomerization rate constants and the activation parameters of interconversion are of great interest. Here, we investigated the stereodynamics of a set of small 1,2-dialkyldiaziridines bearing short substituents (Me, Et, iPr, tBu), using enantioselective dynamic gas chromatography (DGC). Separation of enantiomers of all compounds, including the highly volatile 1,2-dimethyldiaziridine, was achieved using heptakis(2,3-di-O-ethyl-6-O-tert-butyldimethylsilyl)-β-cyclodextrin in 50% PS086 (w/w) as chiral stationary phase in fused silica capillaries with a length of up to 50 m. Measurements at variable temperatures were performed and reaction rate constants were determined using the unified equation of chromatography implemented in the software DCXplorer. The activation barriers at room temperature for 1-(tert-butyl)-2-ethyldiaziridine, ΔG(╪)(298K) = 123.8 kJ mol(-1) (ΔH(╪) = 115.5±2.9 kJ mol(-1), ΔS(╪) = -28±1 J mol(-1) K(-1)), and 1-ethyl-2-isopropyldiaziridine, ΔG(╪)(298K) = 124.2 kJ mol(-1) (ΔH(╪) = 113.1±2.4 kJ mol(-1), ΔS(╪) = -37±2 J mol(-1) K(-1)), were determined, representing some of the highest values observed for nitrogen inversion in diaziridines.
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Affiliation(s)
- Matthias Kamuf
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany
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24
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Interconversion of Stereochemically Labile Enantiomers (Enantiomerization). Top Curr Chem (Cham) 2013; 341:231-69. [DOI: 10.1007/128_2013_453] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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25
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Aresu E, Fioravanti S, Pellacani L, Sciubba F, Trulli L. Water-controlled chiral inversion of a nitrogen atom during the synthesis of diaziridines from α-branched N,N'-dialkyl α-diimines. NEW J CHEM 2013. [DOI: 10.1039/c3nj00780d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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26
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Kamuf M, Rominger F, Trapp O. Investigation of the Rearrangement in Alkyl-Bridged Bis(carbamoyldiaziridine) Derivatives. European J Org Chem 2012. [DOI: 10.1002/ejoc.201200518] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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