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Carbenes and Nitrenes in Reactive Matrices

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Carbenes and Nitrenes in Reactive Matrices Carbenes and Nitrenes in Reactive Matrices Dissertation To obtain the degree of Doctor of natural science (Dr. rer. nat.) by Enrique Méndez Vega from La Habana, Cuba Bochum 2018 This work was carried out from February 2013 to October 2017 at the Department of Organic Chemistry II of the Ruhr-Universität Bochum under the supervision of Prof. Dr. Wolfram Sander. Part of the work reported in this thesis was performed in collaboration with Prof. Dr. Yuan-Pern Lee at the Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University, Taiwan. First Referee: Prof. Dr. Wolfram Sander Second Referee: Prof. Dr. Patrick Nürnberger Day of submission: 28/02/2018 Day of disputation: 05/04/2018 Publications Mieres-Perez, J.; Mendez-Vega, E.; Velappan, K.; Sander, W., Reaction of Triplet Phenylnitrene with Molecular Oxygen. J. Org. Chem. 2015, 80 (24), 11926-11931. Richter, G.; Mendez-Vega, E.; Sander, W., Singlet Halophenylcarbenes as Strong Hydrogen- Bond Acceptors. J. Phys. Chem. A 2016, 120 (20), 3524-32. Mieres-Perez, J.; Henkel, S.; Mendez-Vega, E.; Schleif, T.; Lohmiller, T.; Savitsky, A.; Sander, W., Dinitreno pentaradicals: organic sextet molecules. J. Phys. Org. Chem. 2017, 30 (4). Mendez-Vega, E.; Maehara, M.; Mieres-Perez, J.; Raut, A. H.; Tsuge, M.; Lee, Y.-P.; Sander, W., Hydrogen Activation by Triplet Carbenes, in preparation. Mendez-Vega, E.; Trosien, I.; Maehara, M.; Mieres-Perez, J.; Sander, W., Spin-Selective Hydrogenation of Carbenes, in preparation. Mendez-Vega, E.; Mieres-Perez, J.; Chapyshev, S. V.; Sander, W., Trinitrenes, in preparation. Scientific Meetings Graduate School Solvation Science Autumn Workshop, RUB, 10/2016 (Oral Contribution, Award). Chemistry and Physics at Low Temperature (CPLT 16), France, 07/2016 (Poster). Graduate School Solvation Science Workshop Area A, RUB, 10/2015 (Poster). European Symposium of Organic Reactivity (ESOR 15), Kiel, 07/2015 (Poster, Award). Graduate School Solvation Science Workshop, RUB, 10/2014 (Poster, Award). Graduate School Solvation Science Summer School, RUB, 06/2014 (Poster). International Symposium on Reactive Intermediates and Unusual Molecules (ISRIUM 14), Japan, 04/2014 (Poster). Graduate School Solvation Science Autumn Workshop, RUB, 11/2013 (Poster). International Internship From 05/2015 to 07/2015 in the research group of Prof. Dr. Yuan-Pern Lee at the Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University, Taiwan. Contents Summary ................................................................................................................................... 1 Background .............................................................................................................................. 4 Carbenes ................................................................................................................................. 4 Nitrenes .................................................................................................................................. 7 Carbenes vs. Nitrenes .......................................................................................................... 11 Quantum Tunneling ............................................................................................................. 14 Hydrogenation of Triplet Intermediates .............................................................................. 21 Introduction .......................................................................................................................... 21 Methylene ............................................................................................................................ 23 p-Hydrogen Matrices ....................................................................................................... 24 Calculations ...................................................................................................................... 28 Fluorenylidene ..................................................................................................................... 31 Hydrogen Matrices ........................................................................................................... 31 Deuterium Matrices ......................................................................................................... 33 Calculations ...................................................................................................................... 38 Diphenylcarbene .................................................................................................................. 40 Hydrogen and Deuterium Matrices .................................................................................. 41 p-Hydrogen Matrices ....................................................................................................... 46 Hydrogen-doped Inert Gas Matrices ................................................................................ 51 Calculations ...................................................................................................................... 54 Diphenylcarbene vs. Fluorenylidene................................................................................ 57 Arylnitrenes ......................................................................................................................... 61 Hydrogen Matrices ........................................................................................................... 62 Calculations ...................................................................................................................... 64 Spin-Selective Hydrogenation of Carbenes ......................................................................... 67 Introduction .......................................................................................................................... 67 Bis(p-methoxyphenyl)carbene ............................................................................................. 69 Hydrogen matrices ........................................................................................................... 69 Deuterium matrices .......................................................................................................... 71 Hydrogen-doped Inert Gas Matrices ................................................................................ 77 Calculations ...................................................................................................................... 81 3-Methoxy-9-fluorenylidene ................................................................................................ 84 Hydrogen Matrices ........................................................................................................... 86 Deuterium Matrices ......................................................................................................... 87 Calculations ...................................................................................................................... 90 Trinitrenes .............................................................................................................................. 94 Introduction .......................................................................................................................... 94 1,3,5-Trichloro-2,4,6-trinitrenobenzene .............................................................................. 96 IR Spectroscopy ............................................................................................................... 96 UV–vis Spectroscopy ..................................................................................................... 100 Reactive Matrices ........................................................................................................... 103 1,3,5-Tribromo-2,4,6-trinitrenobenzene ............................................................................ 108 IR and UV–vis Spectroscopy ......................................................................................... 108 Experimental Section ........................................................................................................... 113 Methods ............................................................................................................................. 113 Matrix Isolation .............................................................................................................. 113 Low-Temperature Spectroscopy .................................................................................... 113 Standard Spectroscopy ................................................................................................... 114 Light Sources ................................................................................................................. 114 p-Hydrogen .................................................................................................................... 114 Calculations .................................................................................................................... 115 Synthesis ............................................................................................................................ 115 9-Diazofluorene ............................................................................................................. 115 Diphenyldiazomethane .................................................................................................. 115 Bis(p-methoxyphenyl)diazomethane ............................................................................
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