Synergy between Homogeneous and Heterogeneous Catalysis

Dr. Jagadeesh Rajenahally / Deputy Dr. Narayana Kalevaru

The development of more sustainable processes for advanced organic synthesis continues to be a major goal of chemical research. Notably, catalysis constitutes a key technology for achieving more sustainable processes in the chemical, pharmaceutical, energy and material industries. In this regard, the design of ‘‘ideal’’ catalysts is of central importance for the production of all kinds of chemicals and life-science molecules today and in the future.  

Our Research focuses on:

(1) Development of inexpensive and practical catalysts with the activity and selectivity of the homogeneous ones, and the stability and recyclability of the heterogeneous ones.

(2) Development of more sustainable processes for fine and bulk chemicals as well as molecules related to life-sciences.

Catalyst development

The major challenge in catalysis is to create catalysts that exhibit extreme stability, remarkable activity and high selectivity. In general, homogeneous catalysts are very selective but not stable, whereas heterogeneous catalysts are pretty stable but not selective. Our explorative group is dealing on how to combine both homogeneous and heterogeneous catalysis to create ‘breakthrough’ catalysts to bridge the gap between both of these aspects. As an example, we prepared Fe- and Co-based nanocatalysts by using homogeneous metal complexes and metal organic frameworks as precursors and structure controlling templates. These catalysts are highly stable and selective for hydrogenation, amination and oxidation reactions (See, Science 2013, 342, 1073; Science 2017, 358, 326; Nature Communications 2014, 5, 4123).

“Collectively, our aim is to create very active & stable catalysts with high product selectivity at low cost”.

Sustainable organic synthesis

By using suitable catalysts (mentioned above) we develop sustainable processes for the synthesis of essential chemicals, pharmaceuticals, agrochemicals and biomolecules. For this synthesis, we apply catalytic amination, CH-activation, hydrogenation, dehydrogenation, oxidation and coupling reactions as well as valorization of abundant small molecules and renewables resources.

Currently our main emphasis is on following catalytic processes:

Amination and hydrogenation reactions: Reductive amination, amination of alcohols and aminocarbonylation reactions. Hydrogenation of aromatic hydrocarbons, amides, esters and hydrogenolysis reactions.

C-H activation and functionalization: Site selective C-H functionalization for the refinement of simple and complex molecules. CH-oxidation, CH-amination, CH-(methyl) alkylation and dehydrogenation reactions. CH-silylation, -borylation and -fluorination reactions.

References:

1. Senthamarai, Thirusangumurugan; Murugesan, Kathiravan; Schneidewind, Jacob; Kalevaru, Narayana V.; Baumann, Wolfgang; Neumann, Helfried; Kamer, Paul C. J.; Beller, Matthias; Jagadeesh, Rajenahally V. Nature Communications 2018, 9, 4123. Simple Ruthenium-Catalyzed Reductive Amination Enables the Synthesis of a Broad Range of Primary Amines.

2. Murugesan, Kathiravan; Senthamarai, Thirusangumurugan; Sohail, Manzar; Alshammari, Ahmad S.; Pohl, Marga-Martina; Beller, Matthias; Jagadeesh, Rajenahally V. Chemical Science 2018, 9, 8553-8560. Cobalt-Based Nanoparticles Prepared from MOF-carbon Templates as Efficient Hydrogenation Catalysts.

3. Natte, Kishore; Neumann, Helfried; Beller, Matthias; Jagadeesh, Rajenahally V. Angewandte Chemie International Edition 2017, 56, 6384-6394. Transition-Metal-Catalyzed Utilization of Methanol as a C1 Source in Organic Synthesis.

4. Jagadeesh, Rajenahally V.; Murugesan, Kathiravan; Alshammari, Ahmad S.; Neumann, Helfried; Pohl, Marga-Martina; Radnik, Joerg; Beller, Matthias. Science 2017, 358, 326-332. MOF-derived cobalt nanoparticles catalyze a general synthesis of amines.   

5. Natte, Kishore; Neumann, Helfried; Jagadeesh, Rajenahally V.; Beller, Matthias. Nature Communications 2017, 8, 1334. Convenient iron-catalyzed reductive aminations without hydrogen for selective synthesis of N-methylamines.

6. Jagadeesh, Rajenahally V.; Junge, Henrik; Beller Matthias. Nature Communications 2014, 5, 4123. Green Synthesis of Nitriles Using Non-noble Metal Oxides Based Nanocatalysts.

7. Jagadeesh, Rajenahally V.;  Surkus, Annette-Enrica; Junge, Henrik; Pohl, Marga-Martina; Radnik, Joerg; Rabeah, Jabor;  Huan, Heming; Schuenemann, Volker; Brueckner, Angelika; Beller, Matthias. Science 2013, 342, 1073-1076. Nanoscale Fe2O3-Based Catalysts for Selective Hydrogenation of Nitroarenes to Anilines.

8. Jagadeesh, Rajenahally V.; Junge, Henrik; Pohl, Marga-Martina; Radnik, Joerg; Brueckner, Angelika; Beller, Matthias. Journal of the American Chemical Society 2013, 135, 10776-10782. Selective Oxidation of Alcohols to Esters using Heterogeneous Co3O4-N@C Under Mild Conditions.