FY2021 Annual Report

Coordination Chemistry and Catalysis Unit
Associate Professor Julia Khusnutdinova



In FY2021, we initiated a new project in our group on trifluoromethylation catalyzed by Ni complexes in the presence of light and continued investigation of the organometallic chemistry and reactivity of transition metal complexes with bulky tetramethylated PNP ligand and N3C-pyridinophane. We also reported construction of Pd-Cu-Cu-Pd and Pd-Cu multimetallic complexes using a phosphine-modified multinucleating ligand and published a short invited Frontier article summarizing development of Cu-based molecular probes for molecular stress in polymers using photo- and triboluminescent compounds, which was also featured on the front cover of Dalton Transactions.

1. Staff

  • Dr. Ayumu Karimata, Postdoctoral Scholar
  • Dr. Govindarajan Ramadoss, Postdoctoral Scholar
  • Dr. Dilip Pandey, Postdoctoral Scholar
  • Dr. Janet Bahri, Postdoctoral Scholar
  • Dr. Vardhanapu Pavan Kumar, Research Technician
  • Shubham Deolka, Graduate Student
  • Hoan Dinh, Graduate Student
  • Tatiana Gridneva, Graduate Student
  • Aleksandr Sorvanov, Graduate Student
  • Kyoko Chinen, Research Unit Administrator

2. Collaborations

2.1 The Title or Name or Topic of the Collaboration

  • Type of collaboration: DFT calculations and mechanistic studies of multimetallic complexes
  • Researchers: Dr. Shrinwantu Pal, Professor Kyoko Nozaki, University of Tokyo


3. Activities and Findings

3.1 Photoinduced Ni-catalyzed trifluoromethylation

We developed new simple Ni catalysts supported by simple naphthyridine ligand that catalyzed trifluoromethylation of C-H bonds in arenes and heteroarenes in the presence of blue LED light. A number of simple protocols can be used including trifluoromethylation by Langlois reagent in the presence of oxidant and air, and trifluoromethylation using the Umemoto reagent under mild conditions. Interestingly, the catalyst for these transformation is an unusually stable Ni(III) complex formed by the aerobic oxidation of the Ni(II) precursor simply by oxygen from air. The mechanistic studies showed that the reaction occurs via CF3 radical formation.


3.2 Multimetallic chain construction: ligand and anion control to reverse metal atom ordering

Catalysis and chemical bond activation mediated cooperatively by two different metal is an active area of study in catalysis and coordination chemistry. For example, cooperation between Pd and Cu has been proposed at the transmetalation step in the Sonogashira C-C cross-coupling reaction. However, detailed understanding of the presence of metal-metal interactions and ordering of metals in multimetal chain affects the reactivity of these systems in bond activation is hindered due to synthetic difficulties in selective formation of well-defined multimetallic structures with controlled order and positions of metal atoms. Continuing our ongoing efforts on creating new multinucleating ligand for the controlled construction of multimetallic chains for reactivity studies, we synthetized a phosphine-terminated naphthyridinone-based ligand, which is a “soft”-donor analog of the previously reported bis- and mono-picolylamine-terminated ligand. While previously we reported construction of multicopper and Cu-Pd-Pd-Cu chains, using our new ligand, we reported formation of “inverted” order chains: Pd-Cu-Cu-Pd. Moreover, using coordinating anions, we can modulate the chain formation and obtain selectively binuclear Pd-Cu(Cl) complexes. The reactivity of these complexes with alkyne has also been investigated leading to terminal alkyne C-H bond cleavage with assistance of the ligand. The presence of metal-metal interactions has been analyzed through Natural Bond Orbital and Quantum Theory of Atoms in Molecules analyses.

3.3 Organometallic reactivity and catalysis by pincer and pyridinophane complexes

In FY2021, we decided to put a new bulky tetramethyl PNP ligand on new metals, Co and Ru, to study their stoichiometric and catalytic reactivity. We have shown that Co complexes supported by Me4PNP ligand are catalytically active in hydrogenation of alkenes and internal alkynes. The reactivity of Co with H2 occurs involves a series of two-electron oxidative addition/reductive elimination events, thus enabling selective two-electron reactivity at the first row transition metal while no undesired radical or one-electron redox-reactivity more typical for first row transition metal was observed. This study demonstrates that using appropriate ligand design, selective non-radical reductive elimination/oxidative addition pathways may be enabled using first row metal such as cobalt, which may ultimately open new pathways for utilization of cheaper first row transition metals as replacement for commonly used precious metal catalysts.

Another system in which we report selective, overall two-electron reductive elimination from the paramagnetic first row transition metal involves high valent Mn(III) complexes supported by the cyclometalating N3C pyridinophane ligand. This article was an invited contribution to a special issue of Organometallics “Organometallic Solutions to Challenges in Cross-Coupling”. This study sheds light on the possible use of Mn as a cheap and non-toxic catalyst for C-C cross-cooupling, which is usually catalyzed by more expensive Pd catalysts.

4. Publications

4.1 Journals

  1. He, Y.-T.; Karimata, A.; Gladkovskaya, O.; Khaskin, E.; Fayzullin, R. R.; Sarbajna, A.; Khusnutdinova, J. R. "C-C Bond Elimination from High-Valent Mn Aryl Complexes" Organometallics 2021, 40, 2320-2331. https://doi.org/10.1021/acs.organomet.1c00047 Invited contribution to a special issue "Organometallic Solutions to Challenges in Cross-Coupling"
  2. Rivada-Wheelaghan, O.; Deolka, S.; Govindarajan, R.; Khaskin, E.; Fayzullin, R. R.; Pal, S.; Khusnutdinova, J. R. "Construction of Modular Pd/Cu Multimetallic Chains via Ligand- and Anion-Controlled Metal-Metal Interactions" Chem. Commun. 2021, 57, 10206-10209. https://doi.org/10.1039/D1CC04212B
  3. Deolka, S.; Govindarajan, R.; Khaskin, E.; Fayzullin, R. R.; Roy, M. C.; Khusnutdinova, J. R. "Photoinduced Trifluoromethylation of Arenes and Heteroarenes Catalyzed by High-Valent Nickel Complexes" Angew. Chem. Int. Ed. 2021, 60, 24620-24629. https://doi.org/10.1002/anie.202109953
  4. Lapointe, S.; Pandey, D. K.; Gallagher, J. M.; Osborne, J.; Fayzullin, R. R.; Khaskin, E.; Khusnutdinova, J. R. "Cobalt Complexes of Bulky PNP Ligand: H2 Activation and Catalytic Two-Electron Reactivity in Hydrogenation of Alkenes and Alkynes" Organometallics 2021, 40, 3617-3626 https://doi.org/10.1021/acs.organomet.1c00488
  5. Deolka, S.; Fayzullin, R. R.; Khaskin, E. "Bulky PNP Ligands Blocking Metal-Ligand Cooperation Allow for Isolation of Ru(0), and Lead to Catalytically Active Ru Complexes in Acceptorless Alcohol Dehydrogenation" Chem. Eur. J. 2022, 28, e202103778. https://doi.org/10.1002/chem.202103778
  6. Karimata, A.; Khusnutdinova, J. R."Photo- and triboluminescent pyridinophane Cu complexes: New organometallic tools for mechanoresponsive materials" Dalton Trans. (invited Frontier article) 2022, 51, 3369-3764 DOI: 10.1039/D1DT04305F

4.2 Books and other one-time publications

Nothing to report

4.3 Oral and Poster Presentations

  1. Gridneva, T., Karimata, A. & Khusnutdinova, J., New Photoluminescent Arylamide-Copper(I) Complexes Supported by Macrocyclic Pyridinophane Ligands. in The 71st JSCC Conference: Online, 2021.09.16
  2. Karimata, A. & Khusnutdinova, J., Mechanoresponse of luminescent pyridinophane CuI(NHC)X complexes in polymers. in The 71st JSCC Conference: Online, 2021.09.16
  3. Deolka, S., Ramadoss, G., Khaskin, E. & Khusnutdinova, J. High valent nickel chemistry in naphthyridine ligand system for photoinduced trifluoromethylation reactions, in The 71st JSCC Conference, Online, 2021.09.17
  4. Pandey, D. K., Lapointe, S., Fayzullin, R. R., Khaskin, E. & Khusnutdinova, J. Me4PNP-Cobalt Complexes for H2 Activation and Hydrogenation of Alkenes and Alkynes, in The 71st JSCC Conference, Online, 2022.09.17
  5. Dinh, H. M., Garcia-Roca, A., Gridneva, T., Pruchyathamkorn, J. & Khusnutdinova, J. Single and double dearomatization in N,S-pyridinophane metal complexes, in Pacifichem 2021, Online, 2021.12.20
  6. Gridneva, T., Karimata, A. & Khusnutdinova, J. Study of luminescent Cu(I)-pyridinophane-arylamide complexes and their incorporation into polymer films: towards the development of mechanoresponsive materials, in The 102nd CSJ Annual Meeting, Online, 2022.03.23
  7. Karimata, A., Fayzullin, R. R. & Khusnutdinova, J. Triboluminescence of luminophores in blended polymers: Simple preparation method for triboluminescent films, in The 102nd CSJ Annual Meeting, Online, 2022.03.23
  8. Ramadoss, G., Deolka, S., Khaskin, E., Fayzullin, R. R., Pal, S., Pal, R. & Khusnutdinova, J.  Small-Molecule Activation Driven by Metal-Metal Cooperation in Pt/Base Metal Complexes, in The 102nd CSJ Annual Meeting, Online, 2022.03.23
  9. Pandey, D. K., Fayzullin, R. R & Khusnutdinova, J. Bulky and non-bulky PNP complexes with earth-abundant metals and their hydrogenation reactivity, in The 102nd CSJ Annual Meeting, Online, 2022.03.23
  10. Deolka, S. & Khusnutdinova, J. High valent Nickel catalyzed trifluoromethylation of arenes and heteroarenes induced by light irradiation, in The 102nd CSJ Annual Meeting 2022, Online, 2022.03.24
  11. Khusnutdinova, J.,  Invited talk at Summer School on Organometallic Chemistry, Metal-Metal Cooperation: Building Metal Chains to Make and Break Chemical Bond., Online, 2021.07.04
  12. Karimata, A., Invited talk at The 71th Japanese Society of Coordination Chemistry, Symposium “Interplay between mechanical and physical properties of functional molecular crystals”, Mechanoresponse of luminescent pyridinophane CuI (NHC)X complexes in polymers., Online, 2021.09.16
  13. Karimata, A.,   Invited talk at The society of rubber science and technology, Autumn meeting (日本ゴム協会関西支部秋期ゴム技術講習会), 発光性ピリジノファン銅錯体のポリマー中における機械的刺激応答と摩擦発光,  Online, 2021.10.06
  14. Khusnutdinova, J.,  Invited talk at The 3rd workshop of mechanoluminescence working group: National Institute of Advanced Industrial Science and Technology, Photo- and triboluminescent pyridinophane Cu complexes: New organometallic tools for mechanoresponsive materials.Online, 2022.02.24

5. Intellectual Property Rights and Other Specific Achievements

5.1. Patents

1.    Provisional patent, Japan, Application/Provisional number 2021-143024,  J. R. Khusnutdinova, A. Karimata, "Amorphous triboluminescent material, method for producing the same method for generating light emission in amorphous triboluminescent layer and mechanoresponsive sensor". 

6. Meetings and Events

Nothing to report.


7. Other

JSCC Student Presentation Award 202 to presentation at the 71st JSCC Conference: Deolka, S., Ramadoss, G., Khaskin, E. & Khusnutdinova, J. High valent nickel chemistry in naphthyridine ligand system for photoinduced trifluoromethylation reactions (Online, 2021.09.17).

CSJ Student Presentation Award 2022 to presentation  at the 102nd CSJ meeting: Deolka, S. & Khusnutdinova, J. High  valent  Nickel  catalyzed trifluoromethylation of arenes and heteroarenes induced by light irradiation (Online, 2022.03.24).