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Abstract Oxygen reduction reaction (ORR) is an electrochemical reaction in which dissolved oxygen in an electrolyte is reduced to OH−/H2O when receiving electrons. This reaction plays a crucial role in shaping the efficiency of both metal–air batteries and fuel cells, and precious metals are the dominant catalysts carrying out the ORR in their cathodes. However, how to manipulate the electronic structure of precious metals as active sites to further promote ORR performance and maximize the utilization rate is still under development. Metal oxide serves as suitable and promising support that can strongly interact with precious metals for both activity and durability enhancement. Herein, we present recent research updates on strong precious metal–metal oxide interaction (SPMMOI) utilized in ORR. We start by introducing the background of ORR, the issues to be solved, and its practical applications followed by a thorough discussion of the reaction mechanism and comprehensive evaluation protocols of performance. We then provide a complete understanding of the working principle of SPMMOI and highlight the related advances. Finally, we summarize the merits of the precious metal–metal oxide system and propose the research direction as well as some urgent problems to be addressed in the future.
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Applications of catalysis in hydroboration of imines, nitriles, and carbodiimides
The catalytic hydroboration of imines, nitriles, and carbodiimides is a powerful method of preparing amines which are key synthetic intermediates in the synthesis of many value-added products. Imine hydroboration has perennially featured in notable reports while nitrile and carbodiimide hydroboration have gained attention recently. Initial developments in catalytic hydroboration of imines and nitriles employed precious metals and typically required harsh reaction conditions. More recent advances have shifted toward the use of base metal and main group element catalysis and milder reaction conditions. In this survey, we review metal and nonmetal catalyzed hydroboration of these unsaturated organic molecules and group them into three distinct categories: precious metals, base metals, and main group catalysts. The TON and TOF of imine hydroboration catalysts are reported and summarized with a brief overview of recent advances in the field. Mechanistic and kinetic studies of some of these protocols are also presented.
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- Award ID(s):
- 1934725
- PAR ID:
- 10388970
- Date Published:
- Journal Name:
- Organic & Biomolecular Chemistry
- Volume:
- 20
- Issue:
- 18
- ISSN:
- 1477-0520
- Page Range / eLocation ID:
- 3675 to 3702
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D2OB00162D
