Publikationen

U. Wild, O. Hübner, S. Jaworski, E. Kaifer, H.-J. Himmel*

Chem. Eur. J. 2026, in press (DOI: 10.1002/chem.70981)

Hydroquinone Oxidation by Redox-active Guanidines and Thioguanidines: Faster Conversion to High-Potential than Low-Potential Quinones 

C.L.M. Henel, E. Michel, D. Zeitler, O. Hübner, E. Kaifer, H.-J. Himmel*

Chem. Eur. J. 2025,

e202503147

Triggering and Preventing Cyclization of o-Amino-Guanidinobenzenes to 2-Amino-Benzimidazoles

F. Kreis, A. Poddelskii, L. Hammermüller, P. Bootz, F. Bodenmüller, E. Kaifer, A. Köhn*, H.-J. Himmel*

Chem. Eur. J. 2025, 

e202503160

Bistability in Palladium Complexes with Two Different Redox-Active Ligands of Orthogonal Charge Regimes

E. Engels, H. Koepcke, M. Lörsch, P. Römgens, A.K. Helm, S. Leingang, E. Kaifer, H.-J. Himmel*

Chem. Eur. J. 2025,

e202502457

Steric Restraints in Redox-Active Guanidine Ligands and Their Impact on Coordination

M. Schulz, A. Poddelskii, H. A. Bohnert, F. Eckhardt, L. Hirner, S. Leingang, E. Kaifer, H.-J. Himmel*

Eur. J. Inorg. Chem. 2025,

e202500346

Variation of the Redox Properties and Coordination Chemistry of Redox-Active Aromatic Diguanidine Ligands with the Substitution Pattern

J. Osterbrink, M. Kaliske, M. Schulz, H. Koepcke, O. Hübner, E. Kaifer, H.-J. Himmel*

Chem. Eur. J. 2025,

Fine Tuning of the Redox-Active Diguanidine Ligand in Cationic Cobalt Complexes for Electronic Structure Control

H.-J. Himmel*

Eur. J. Inorg. Chem. 2025, 

ejic.202500214

Boron-Boron Single Bonds Mimicking Transition Metals

O. Hübner, H.-J. Himmel*

Chem. Eur. J. 2025, 

e202500432

Dinitrogen Splitting Without Barrier of Visible Light Driven: Reactions of Vanadium Trimers an Dimers with Dintrogen

L.Haas, L. Kistner, E.A.M. Roesky, L. Mailänder, E. Kaifer, H.-J. Himmel*

Chem. Eur. J. 2025,

D. Vogler, J. Krauss, T. Kaczun, G. Dulatahu, E. Kaifer, H.-J. Himmel*

Chem. Eur. J. 2024,

e202404584

D. Ehjeij, J. Kopping, C. Gabriel, J.R. Wünsch, H.-J. Himmel, R.R. Schröder, M. Wilhelm, J. Freudenberg, U.H.F. Bunz, K. Müllen*

Macromol. Chem. Phys. 2024, 2400320

Electrochemical Exfoliation of Graphene and Formation of its Copolyamide 6/66 Nanocomposites by Wet Phase Inversion and Injection Molding

U. Wild, E. Engels, O. Huebner, E. Kaifer, H.-J. Himmel*

Chem. Eur. J. 2024, e202403080

Redox-Induced Aromatic Substitution: A Study on Guanidino-Functionalized Aromatics

P. Walter, M. Schulz, O. Huebner, A. Poddelskii, E. Kaifer, H.-J. Himmel*

Chem. Eur. J. 2024, e202402917

Dehydrogenative Coupling Reactions with Guanidino-Functionalized Aromatics

S.L. Holzmann, J. Osterbrink, O. Hübner, E. Kaifer, H.-J. Himmel*

Eur. J. Inorg. Chem. 2024, e202400597

Tuning of the Electronic Structure and Reactivity of Metal Complexes with Redoc-Active Guanidine Ligands

S. Kar, S., Bairagi, G. Joshi, E.D. Jemmis*, H.-J. Himmel*, S. Gosh*

Acc. Chem. Res. 2024

Small Ring Molecules Comprising 3-6 Boron Atoms: An Account on Synthesis, Structure, and Orbital Engineering

D. Vogler, J. Horn, E. Kaifer, H.-J. Himmel*

Eur. J. Inorg. Chem. 2024, e202400479

Small Cationic Boron and Boron-Nitrogen Rings, Synthesized from Diboranes with Charge-Delocalizing Guanidinate Substituents

S. Haaf, C.M. Henel, F. Kreis, M. Bruttel, E. Kaifer, J. Osterbrink, O. Hübner,  H.-J. Himmel*

Eur. J. Inorg. Chem. 2024, e202400299

Redox and Coordination Chemistry of Diguanidino-Benzene Ligands with Crown Ether Functions as Secondary Coordination Speres

S. Germer, M. Bauer, O. Hübner, A. Dreuw, H.-J. Himmel*

Chem. Eur. J. 2024, e202401340

Aggregation of N-Heteropolycyclic Aromatic Molecules: The Acridine Dimer and Trimer

J. Osterbrink, F. Dos Santos, E. Kaifer, H.-J. Himmel*

Eur. J. Inorg. Chem. 2024, e202400070 (1 of 11)

Redox Reactivity Control Through Electromerism

H.-J. Himmel

Chapter 7(p. 199 - 248) in Redox-Active Ligands: Concepts and Catalysis, Ed. M. Desage-El Murr, Wiley 2024, ISBN: 978-3-527-34850-3

Redox-Active Guanidine Ligands

L. Gerhards, M. Werr, O. Hübner, I.A. Solov'yov, H.-J. Himmel

Inorg. Chem. 2024, 63, 961-975

Peculiar Differences of Two Copper Complexes Containing Similar Redox-Active Ligands: Density functional and Multiconfigurational Calculations

L. Kistner, L.M. Sigmund, F.F. Grieser, J. Krauß, S. Leingang, E. Kaifer, L. Greb, H.-J. Himmel*

Angew. Chem. Int. Ed. 2023, e202317462

Metal-Free B-B Dehydrocoupling Reaction of a Simple Borane Adduct: Convenient Access to a Nucleophilic Diborane(4)

S. Germer, M. Bauer, O. Hübner, R. Marten, A. Dreuw, H.-J. Himmel

Chem. Eur. J. 2023, e202302296

Isolated Dimers Versus Solid-State Dimers of N-Heteropolycycles: Matrix-Isolation Spectroscopy in Concert with Quantum Chemistry

D. Vogler, M. Schenker, K. H. Ng, E. Kaifer, H.-J. Himmel

Eur. J. Inorg. Chem. 2023, e202300565

On the Coordination Chemistry of Triazolyl-substituted Diborane Ligands, Prepared by 1,3-dipolar Cycloaddition Reactions between Diazido-diboranes and Alkynes

S. Haaf, E. Engels, E. Kaifer, H.-J. Himmel

Chem. Eur. J. 2023, e202301903

Hexaguanidino-Triptycenes and Triphenylenes: Electronic Coupling in Molecules Containing Three Redox-Active o-Diguanidinobenzene Units Connected Either Directly or Interacting Through Homoconjugation

245

E. Filbeck, S. Cremer, M.C.F, Jansen, E. Kaifer, H.-J. Himmel*

Chem. Eur. J. 2023, e202302911

Halide-Coupled Double Electron Transfer with Electron-Rich Diboranes

U. Wild, O. Hübner, P. Meiners, E. Kaifer, M. Enders*,  H.-J. Himmel*

Chem. Eur. J. 2023, e202302418

Intramolecular Through-Space Double-Electron Transfer Between A Pair of Redox-Active Guanidine Units Aligned by Dithiolate Bridges

J. Osterbrink, P. Walter, S. Leingang, H. Pfisterer, E. Kaifer, H.-J. Himmel*

Chem. Eur. J. 2023, e202300514

Quantitastive Electromerism of a Well-defined Mononuclear Copper Complex Through Reversible Intramolecular Metal-Ligand Electron Transfer

L. Kistner, E. Filbeck, P. Ihle, Bučak Gasser, S.W. H. Häussermann, D. Kowatsch, E. Kaifer, H.-J. Himmel*


Eur. J. Org. Chem. 2023, e202300038

Cationic Symmetrically and Unsymmetrically Substituted Diboranes and Bis(diboranes) with Direct Boron-Boron Bond: Synthesis by Substitution, Stability and Properties

O. Hübner, J. Thusek, H.-J. Himmel*

Angew. Chem.Int. Ed.2023,e202218042

Pyridine Dimers and Their Low-Temperature Isomerization: A High-Resolution Matrix-Isolation Spectroscopy Study  

E. Filbeck, L. Kistner, D. Vogler, D. Bučak Gasser, L. F. Martins, M. Schöner, E. Kaifer, H.-J. Himmel*

Eur. J. Org.Chem.2022, e202201105 (1 - 12)

Synthesis of Symmetrically and Unsymmetrically Substituted Cationic Diborane(4) Compounds with Distinct Structural Motifs and Properties

L. Lohmeyer, M. Werr, E. Kaifer, H.-J. Himmel*

Chem. Eur. J. 2022,e202201789 (1 - 15)

Interplay and Competition Between Two Different Types of Redox-Active Ligands in Cobalt Complexes: How to Allocate the Electrons? 

D. Vogler, M. Schöner, E. Kaifer, H.-J. Himmel*

Chem. Eur. J. 2022,e202201389 (1 - 7)

Bistriazoles Connected Through a B-B Bridge, Synthesized by Highly Selective Dipolar Cycloaddition Reactions of a Diazido-diborane(4)

L. Lohmeyer, E. Kaifer, H.-J. Himmel*

Inorg. Chem. 2022, 61, 8440-8454

Solvent Induced Redox Isomerism of Cobalt Complexes with Redox-Active Bisguanidine Ligands

U. Wild, O. Hübner, M. Enders, E. Kaifer, H.-J. Himmel

Eur. J. Org.Chem.2022, e202200349 (1 - 18)

Connecting Organic Redox-Active Building Blocks Through Mild Non-Catalytic C-H Activation

L. Kistner, D. Kowatsch, A. Marz, E. Kaifer,  H.-J. Himmel*

Chem. Eur. J. 2022,e202104016 (1 - 17)

Directed Synthesis and Chemistry of Unsymmetric Dicationic Diboranes and Their Use in Frustrated Lewis Pair-like Chemistry

L. Steuer, E. Kaifer,  H.-J. Himmel*

Eur. J. Org.Chem.2022, e202101360 (1 - 15)

Redox-Active Dendrimer-Like Oligoguanidines and Their Use in a Proton-Coupled Electron Transfer Reaction
 

D. Vogler, L. Haas, N. Wolf, E. Kaifer,  H.-J. Himmel*

Chem. Commun., 2022, 58, 693-696

Derivatization of an especially electron-rich diborane

E. Filbeck, A. Widera,  E. Kaifer, H.-J. Himmel*

Chem. Eur. J. 2021, 27, 15737 -15750 

Polycationic Redox-Active Cyclophanes with  Integrated Electron-Rich Diboron Units

M. Werr, E. Kaifer, M. Enders, A. Asyuda., M. Zharnikov, H.-J. Himmel*

Angew. Chem.Int. Ed, 2021, 60, 23451-23462

A Copper(I) Complex with Two Unpaired Electrons, Synthesised by Oxidation of a Copper(II) Complex with Two Redox-Active Ligands

O. Hübner, H.-J. Himmel*

Z. Anorg. Allg. Chem. 2021, 647, 1764 - 1777

The Dioxygen Complexes of VO₂

Dedicated to Prof. Dr. Hansgeorg Schnöckel on the occasion of his 80th birthday

P. Walter, O. Hübner, E. Kaifer,  H.-J. Himmel*

Chem. Eur. J. 2021, 27, 11943-11956 

Proton-Coupled Electron Transfer (PCET) with 1,4-Bisguanidino-Benzene Derivatives: Comparative Study and Use in Acid-Initiated  C-H Activation

L. Steuer, E. Kaifer, H.-J. Himmel*

Dalton Trans. 2021 50, 9467 - 9482

On the Metal-Ligand Bonding in Dinuclear Complexes with Redox Active Guanidine Ligands

L. Lohmeyer, E. Kaifer, M. Enders,  H.-J. Himmel*

Chem. Eur. J. 2021, 27, 11852-11867

Switching from Metal- to Ligand-Based Oxidation in Cobalt Complexes with Redox-Active Bisguanidine Ligands

S. Schneider, J. M. Gotthardt, L. Steuer, S. Leingang, H.-J. Himmel, J. Zaumseil*;

J. Mater. Chem. C. 2021, 9, 7485 - 7493 

Improving Electron Injection and Transport in Polymer Field-Effect Transistors with Guanidino-Functionalized Aromatic n-Dopants

L. Lohmeyer, F. Schön, E. Kaifer, H.-J. Himmel*, 

Angew. Chem. 2021, 133, 10506 – 10514; Angew. Chem.Int. Ed, 2021, 60, 10415-10422

Stimulation of Redox-Induced Electron Transfer by Interligand Hydrogen Bonding in a Cobalt Complex with Redox-Active Guanidine Ligand

J. Thusek, M. Hoffmann, O. Hübner, S. Germer, H. Hoffmann, J. Freudenberg, U. H. F. Bunz*, A.. Dreuw*, H.-J. Himmel*,

Chem. Eur. J. 2021, 27, 2072-2081

High-Resolution Electronic Excitation and Emission Spectra of Pentacene and 6,13-Diazapentacene Monomers and Weakly Bound Dimers by Matrix-Isolation Spectroscopy

J. Gotthardt, S. Schneider, M. Brohmann, S. Leingang, E. Sauter, M. Zharnikov, H.-J. Himmel, J. Zaumseil*,

ACS Appl. Electron. Mater., 2021, 3, 804-812

Molecular n-Doping of Large- and Small-Diameter Carbon Nanotube Field-Effect Transistors with Tetrakis(tetramethylguanidino)benzene

S. Haaf. E. Kaifer, H. Wadepohl, H.-J. Himmel*, 

Chem. Eur. J. 2021, 27, 959-970

Very important paper

Use of Crown Ether Functions as Secondary Coordination Spheres for the Manipulation of Ligand-Metal Intramolecular Electron Transfer in Copper-Guanidine Complexes

M. Statz, S. Schneider, F. J. Berger, L. Lai, W. A. Wood, M. Abdi-Jalebi, S. Leingang, H.-J. Himmel, J. Zaumseil*, H. Sirringhaus*, 

ACS Nano 2020, 14, 15552-15565

Charge and Thermoelectric Transport in Polymer-Sorted Semiconducting Single-Walled Carbon Nanotube Networks

U. Wild, P. Walter, O. Hübner, E. Kaifer, H.-J. Himmel*,

Chem. Eur. J. 2020, 26, 16504-16513

Evaluation of the Synthetic Scope and the Reaction Pathways of Proton-Coupled Electron Transfer with Redox-Active Guanidines in C-H Activation Processes

A. Widera, E. Filbeck, H.-J. Himmel, 

Eur. J. Inorg. Chem. 2020, 3017-3029

Chemistry of Dicationic Diboranes

C. Wagner, F. Kreis, D. Popp, O. Hübner, E. Kaifer, H.-J. Himmel*,

Chem. Eur. J. 2020, 26, 10336-10347

1,2,4,5-Tetrakis(tetramethylguanidino)-3,5-diethynyl-benzenes: Fluorescent Probes, Redox-Active Ligands and Strong Organic Electron Donors

O. Hübner, H.-J. Himmel*

Angew. Chem. 2020, 132, 12304-12310; Angew. Chem. Int. Ed. 2020, 59, 12206-12212.

Hot Paper 

Oxidative Addition of Dihydrogen to Divanadium in Solid Ne: Multiple-Bonded Triplet HVVH and Singlet V₂(μ-H)₂

M. Werr, E. Kaifer, H.-J. Himmel*,

Chem. Eur. J. 2020, 26, 12328-12332

Hetero Diels-Alder Reactions with a Dicationic Urea Azine Derivated Azo Dienophile and Their Use for the Synthesis of an Electron-Rich Pentacene

F. Schön, L. Greb, E. Kaifer, H.-J. Himmel*,

Angew. Chem. 2020, 132, 9212-9218; Angew. Chem. Int. Ed. 2020, 59, 9127-9133

Hot Paper

Desymmetrisation of Dicationic Diboranes by Isomerization Catalysed by a Nucleophile

L. Lohmeyer, E. Kaifer, H. Wadepohl, H.-J. Himmel*,

Chem. Eur. J. 2020, 26, 5834-5845

1,2,5,6-Tetrakisguanidino-naphthalenes: Electron Donors, Fluorescent Probes, and Redox-Active Ligands

A. Widera, E. Filbeck, H. Wadepohl, E. Kaifer, H.-J. Himmel*,

Chem. Eur. J. 2020, 26, 3435-3440

Electron-Rich, Lewis Acidic Diborane Meets N-Heterocyclic Aromatics: Formation and Electron Transfer in Cyclophane Boranes

U. Wild, O. Hübner, H.-J. Himmel*, 

Chem. Eur. J. 2019, 25, 15988-15992

Redox-active Guanidines in Proton-Coupled Electron Transfer Reactions: Real Alternatives to Benzoquinones?

P. Walter, E. Kaifer, H. Herrmann, H. Wadepohl, O. Hübner, H.-J. Himmel*, 

Eur. J. Inorg. Chem. 2019, 4147-4160

Redox-Active Guanidines with One or Two Guanidino Groups and their Integration in Low-dimensional Perovskite Structures

D. Vogler, N. Wolf, E. Kaifer, H.-J. Himmel*,

Dalton Trans. 2019, 48, 14354-14366

Electron Transfer in Complexes of B^II Cations with Organic p-acceptors: A Combined Experimental and Quantum-chemical Study

J. Thusek, M. Hoffmann, O. Hübner, O. Tverskoy, U.H.F. Bunz*, A. Dreuw, H.-J. Himmel*,

Chem. Eur. J. 2019, 25, 15147-15154

Low-energy Electronic Excitations of N-substituted Heteroacene Molecules: Matrix Isolation Spectroscopy in Concert with Quantum-chemical Calculations

M. Werr, E. Kaifer, H. Wadepohl, H.-J. Himmel*

Chem. Eur. J. 2019, 25, 12981-12990

Tuneable Redox-Chemistry and Electrochromism of Persistent Symmetric and Asymmetric Azine Radical Cations

F. Schön, F. Biebl, L. Greb, S. Leingang, B. Grimm-Lebsanft, M. Teubner, S. Buchenau, E. Kaifer, M. A. Rübhausen, H.-J. Himmel*

Chem. Eur. J. 2019, 25, 11257-11268

On the Metal Cooperativity in a Dinuclear Copper-Guanidine Complex for Aliphatic C-H Bond Cleavage by Dioxygen

F. Schön, E. Kaifer, H.-J. Himmel*

Chem. Eur. J. 2019, 25, 8279-8288

Hot Paper

Catalytic Aerobic Phenol Homo- and Cross-Coupling with Copper Complexes Bearing Redox-Active Guanidine Ligands

J. Elias, E. Kaifer, H.-J. Himmel*,

Chem. Eur. J. 2019, 25, 6553-6561

Hot Paper

Boron-Boron Dehydrocoupling of Boranes, Initiated by Reaktion with Iodine

H.-J. Himmel*

Angew. Chem. 2019, 131, 11724-11742; Angew. Chem. Int. Ed. 2019, 58, 11600-11617

Electron-Deficient Triborane and Tetraborane Ring Compounds: Synthesis, Structure and Bonding

C. Wagner, O. Hübner, E. Kaifer, H.-J. Himmel*

Chem. Eur. J. 2019, 25, 3781-3785

Probing the Proton-Coupled Electron Transfer Reactivity of a Cross-Conjugated Cruciform Chromophore by Redox-State Dependent Fluorescence

A. Widera, H. Wadepohl, H.-J. Himmel*

Angew. Chem. 2019, 131, 5957-5961, Angew. Chem. Int. Ed. 2019, 58, 5897-5901

Four Boron Atoms, Four Positive Charges and Four Skeletal Electrons: A Fluorescent sigma-Aromatic Tetraborane(4)