Secondary Interactions in Symmetric Double Bond Formation Catalysed by Molecular Ruthenium Complexes Oleksandr Kravchenko Doctoral Thesis Stockholm 2020 Akademisk avhandling som med tillstånd av Kungliga Tekniska Högskolan i Stockholm framlägges till offentlig granskning för avläggande av doktorsexamen i kemi onsdagen den 14:e oktober kl 13.00 i Kollegiesalen, KTH, Brinellvägen 8, Stockholm. Avhandlingen försvaras på engelska. Opponent är Prof. Roger Alberto, University of Zurich. I ISBN 978-91-7873-638-6 TRITA-CBH-FOU-2020:42 © Oleksandr Kravchenko, 2020 Printed by: Universitetsservice US AB, Sweden 2020 II Oleksandr Kravchenko, 2020: “Secondary Interactions in Symmetric Double Bond Formation Catalysed by Molecular Ruthenium Complexes”, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH – Royal Institute of Technology, SE-100 44 Stockholm, Sweden. Abstract Chemistry has a tremendous impact on everyone’s life, although society does not always realize its power and ubiquity. In recent years, improved economy and sustainability of chemical processes has become a worldwide priority. Since its discovery, catalysis has been leveraged in industry to decrease energy demands in chemical reactions and reduce their cost. This thesis focuses on two catalytic transformations and various aspects of catalyst design that improve the catalytic efficiency and applicability. The first chapter contains an introduction of important concepts in catalysis and an overview of weak interactions, often used when designing catalysts. As symmetry plays a big role in chemistry in general and especially in the reactions discussed in this thesis, a brief overview of some symmetry aspects in molecules and reactions is provided. The second chapter addresses applications of olefin metathesis in dynamic chemistry. The catalysts for establishing equilibria in simple dynamic systems under mild conditions are analysed from a structure-activity relationship perspective. An ability to perform self- and cross-metathesis of functionalized substrates in water is evaluated and used to improve selectivity. The following chapters focus on water oxidation catalysis, which is an essential part of solar fuel generation and the development of sustainable energy solutions. Therefore, the third chapter focuses on the electronic effects in functionalized catalysts. The influence of substituents and backbone modifications on the properties of the catalysts is discussed. The fourth chapter introduces novel design of axial and equatorial ligands in state-of-the-art water oxidation catalysts for improvements in catalytic activity and stability. The research presented in this thesis demonstrates the influence of weak intra- and intermolecular interactions on catalysis and the strategies of using these interactions in transition metal complexes to improve catalytic properties. Keywords: homogeneous catalysis, transition metal catalysis, ruthenium catalyst, olefin metathesis, dynamic covalent chemistry, water oxidation, solar fuels, Ru-bda, secondary interactions, hydrophobic interactions, π-π stacking. III Sammanfattning på svenska Kemi har en enorm påverkan på allas liv även om samhället inte inser dess kraft och allmänna utbredning. Under de senaste åren har ekonomi och hållbarhet i kemiska processer blivit en världsomfattande prioritering. Ända sedan dess upptäckt har katalys utnyttjats i industrin för att minska energibehovet i kemiska reaktioner. Den här avhandlingen behandlar två katalytiska transformationer och olika aspekter av katalysatordesign som förbättrar den katalytiska effektiviteten och användbarheten. Det första kapitlet innehåller en introduktion av viktiga begrepp inom katalys och en översikt över svaga interaktioner som ofta används i katalysatordesign. Eftersom symmetri spelar en stor roll i kemi i allmänhet och särskilt i de reaktioner som diskuteras i den här avhandlingen ges också en kort översikt av vissa symmetriaspekter i molekyler och reaktioner. Det andra kapitlet behandlar tillämpningar av olefinmetatesen i dynamisk kemi. Katalysatorerna för etablering av jämvikt i enkla dynamiska system under milda förhållanden analyseras i en struktur-aktivitetsförhållande studie. Förmågan att utföra själv- och korsmetates av mycket funktionaliserade substrat i vatten utvärderas och används för att öka selektivitet. Följande kapitel fokuserar på vattenoxidationskatalys som är en väsentlig del för produktionen av solbränsle och utvecklingen av hållbar energi. Det tredje kapitlet fokuserar på de elektroniska effekterna i funktionaliserade katalysatorer. Påverkan av substituenter och andra modifikationer på katalysatorernas egenskaper diskuteras. Det fjärde kapitlet introducerar ny design av axiella och ekvatoriella ligander i toppmoderna vattenoxidations-katalysatorer och betydande förbättringar av katalytisk aktivitet och stabilitet. Forskningen som presenteras i den här avhandlingen demonstrerar påverkan av svaga intra- och intermolekylära interaktioner på katalys och sätten att använda dessa interaktioner i övergångsmetallkomplex för att förbättra katalytiska egenskaper. Nyckelord: homogen katalys, övergångsmetallkatalys, rutheniumkatalysator, olefinmetates, dynamisk kovalent kemi, vattenoxidation, solbränslen, Ru-bda, sekundära interaktioner, hydrofoba interaktioner, π-π stapling. IV Abbreviations Ac acetyl bda [2,2'-bipyridine]-6,6'-dicarboxylate biqa [1,1'-biisoquinoline]-3,3'-dicarboxylate Bnd benzylidenyl bpa [2,2'-bipyrazine]-6,6'-dicarboxylate Brisq 6-bromoisoquinoline Bu n-butyl CAAC cyclic (alkyl)(amino)carbene CM cross-metathesis Cy cyclohexyl DFT density functional theory dmbda 4,4'-dimethoxy-[2,2'-bipyridine]-6,6'-dicarboxylate DMF N,N-dimethylformamide DMSO dimethylsulfoxide DNA deoxyribonucleic acid dnbda 4,4'-dinitro-[2,2'-bipyridine]-6,6'-dicarboxylate Et ethyl HMDS hexamethyldisilazide HOMO highest occupied molecular orbital I2M inter/intramolecular coupling of two metal-oxo units Ind 3-phenylindenylidenyl iPr isopropyl Ipy 4-iodopyridine iso-biqa [3,3'-biisoquinoline]-1,1'-dicarboxylate Me methyl MS mass spectrometry NHC N-heterocyclic carbene NHE normal hydrogen electrode NMR nuclear magnetic resonance pda 1,10-phenanthroline-2,9-dicarboxylate PEG pentaethylene glycol Ph phenyl pic 4-picoline pKa negative logarithm of acid dissociation constant ppa 6-(6-carboxylatopyridin-2-yl)pyrazine-2-carboxylate RCM ring-closing metathesis SM self-metathesis Tf trifluoromethanesulfonate TFE 2,2,2-trifluoroethanol TOF turnover frequency TON turnover number WNA water nucleophilic attack V List of Publications This thesis is based on the following papers, referred to in the text by their Roman numerals I–VI: I. Stable CAAC-based Ruthenium Complexes for Dynamic Olefin Metathesis Under Mild Conditions Kravchenko, O., Timmer, B.J.J., Biedermann, M., Inge, A.K. and Ramström, O. Submitted II. Selective Cross-Metathesis of Highly Chelating Substrates in Aqueous Media Timmer, B.J.J., Kravchenko, O. and Ramström, O. ChemistrySelect 2020, 5, 7254–7257 III. Modulation of the First and Second Coordination Sphere Effects by Backbone Substitution in Ru(bda)L2 Water Oxidation Catalysts Kravchenko, O., Timmer, B.J.J., Liu, T., Karalius, A., Zhang, B. and Sun, L. Manuscript in preparation IV. Electronic Influence of the 2,2'-Bipyridine-6,6'-dicarboxylate Ligand in Ru-based Type Water Oxidation Catalysts Timmer, B.J.J., Kravchenko, O., Zhang, B., Liu, T. and Sun, L. Submitted V. Improving the Stability of Ru-bda Molecular Water Oxidation Catalysts via π-System Extension of Backbone Ligand Kravchenko, O., Timmer, B.J.J., Liu, T., Zhang, B. and Sun, L. Submitted VI. Off-set Interactions for Low Concentration Water Splitting Catalysis with Ru(bda)L2 Timmer, B.J.J., Kravchenko, O., Liu, T., Zhang, B. and Sun, L. Submitted VI Papers not included in this thesis: I. Effects of Molecular Modifications for Water Splitting Enhancement of BiVO4 Grądzka-Kurzaj, I., Meng, Q., Timmer, B.J.J., Kravchenko, O., Zhang, B., Gierszewski, M. and Ziółek, M. Int. J. Hydrog. Energy 2020, 45, 15129–15141 II. Switching O–O Bond Formation Mechanism between WNA and I2M Pathways by Modifying the Ru-bda Backbone Ligands of Water-Oxidation Catalysts Zhang, B.*, Zhan, S.*, Liu, T., Wang, L., Inge, A.K., Duan, L., Timmer, B.J.J., Kravchenko, O., Li, F., Ahlquist, M.S.G. and Sun, L. J. Energy Chem. 2021, 54, 815–821 III. Formation and Out-of-Equilibrium, High/Low State Switching of a Nitroaldol Dynamer in Neutral Aqueous Media Karalius, A., Zhang, Y., Kravchenko, O., Elofsson, U., Szabó, Z., Yan, M. and Ramström, O. Angew. Chem. Int. Ed. 2020, 59, 3434–3438 IV. A Robotics-Inspired Screening Algorithm for Molecular Caging Prediction Kravchenko, O.*, Varava, A.*, Pokorny, F.T., Devaurs, D., Kavraki, L.E. and Kragic, D. J. Chem. Inf. Model. 2020, 60, 1302–1316 V. Bio-Inspired Water Oxidation Catalysts Zhang, B., Kravchenko, O. and Sun, L. In: Comprehensive Coordination Chemistry III, Elsevier, 2021 Accepted VI. Recent Progress in Nonprecious Water Oxidation Catalysts for Acidic OER Yang, H., Liu, T., Kravchenko, O., Meng, Q., Li, F. and Sun, L. Submitted VII. Isolated Pseudo Seven-Coordinate RuIII-bda Water Oxidation Catalyst with a “Ready-To-Go” Aqua Ligand Liu, T., Shen, N., Wang, L., Timmer, B.J.J., Li, G., Zhou, S., Ahlquist, M.S.G., Zhang, B., Kravchenko, O., Xu, B. and Sun, L. Submitted VII VIII. 2D MnOx Composite Catalysts Inspired by Natural OEC for Efficient Catalytic Water Oxidation Fan, L.*, Zhang, B.*, Zhang, F., Timmer, B.J.J., Kravchenko, O., Pan, J. and Sun, L. Submitted