A metal-organic framework immobilised iridium pincer complex.

Area of Science:

• Catalysis
• Materials Science
• Coordination Chemistry

Background:

• Metal-organic frameworks (MOFs) offer tunable porous structures for catalyst immobilization.
• Iridium pincer complexes are highly active catalysts for hydrogenation reactions.
• Heterogenization of homogeneous catalysts can improve stability and recyclability.

Purpose of the Study:

• To immobilize an iridium pincer complex within the NU-1000 MOF using solvent assisted ligand-incorporation (SALI).
• To evaluate the catalytic activity and stability of the immobilized iridium complex for condensed phase hydrogenation.
• To compare the performance of the heterogeneous catalyst with its homogeneous analogue.

Main Methods:

• Solvent Assisted Ligand Incorporation (SALI) for immobilizing iridium pincer complex in NU-1000.
• Spectroscopic techniques to confirm the formation of the active iridium dihydride species.
• Condensed phase hydrogenation of alkenes (1-decene and styrene) under various conditions.

Main Results:

• Successful immobilization of the iridium pincer complex within NU-1000.
• The modified NU-1000 framework remained stable during catalyst activation.
• Spectroscopic evidence confirmed the formation of the catalytically active iridium dihydride.
• The heterogeneous catalyst exhibited enhanced activity for alkene hydrogenation compared to homogeneous iridium catalysts.
• Efficient catalytic performance was observed under continuous flow conditions.

Conclusions:

• The NU-1000 MOF effectively immobilizes iridium pincer complexes, creating a stable and active heterogeneous catalyst.
• The immobilized catalyst shows superior performance in condensed phase alkene hydrogenation, including under flow conditions.
• This approach offers a promising strategy for developing robust and efficient catalytic systems.