IrIII-catalyzed dehydrogenative methanol activation and its applications: a success towards hydrogen economy Nidhi Garg , Rinaldo Poli, Basker Sundararaju Department of Chemistry, Indian Institute of Technology Kanpur, India Liquid Organic Hydrogen Carriers (LOHC) are an attractive solution towards long-term hydrogen storage and straightforward transportation, unlike liquified hydrogen (high security requirements) and metal hydrides (packing limitations and limited reversibility). 1 Among various LOHCs, methanol has high hydrogen content (12.5% w/w) and provides abundant possibilities for hydrogen production. However, its endothermal dehydrogenation (63 kJ/mol) and the purification of the liberated hydrogen from the CO 2 and CO co-products are a concern. 2 The selection of a suitable transition-metal catalyst could help the development of a CO/CO 2 -free hydrogen production at mild temperatures. 2 Transition metal-catalyzed hydrogen transfer reactions are viable practical alternatives to direct hydrogenation reactions as they avoid using special reactors, hazardous gas, etc . In this regard, we have recently reported the homogeneous Ir III -bipyridonate-catalyzed chemoselective transfer hydrogenation of ketones and chalcones in the presence of catalytic amount of base using methanol under mild reaction conditions; including its application in late-stage functionalisation. 3-4 Our more recent work has addressed the detailed mechanism of these reactions, including spectroscopic, kinetic and computational work. Notably, a pH-dependent reversible interconversion between two metal-hydride species is noticed. 5 References 1. D. Wang, D. Astruc, Chem. Rev. , 2015, 115 , 6621-6686. N. Garg, A. Sarkar, and B. Sundararaju, Coord. Chem. Rev., 2021, 433 , 213728. 2. N. Garg, S. Paira, and B. Sundararaju, ChemCatChem , 2020, 12 , 3472–3476. 3. N. Garg, H.-P. Somasundharam, P. Dahiya, and B. Sundararaju, Chem. Commun ., 2022, 58 , 9930–9933. 4. N. Garg, R. Poli, and B. Sundararaju, manuscript under preparation.
P10
© The Author(s), 2023
Made with FlippingBook Learn more on our blog