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Tuning the Acidity of Pt/ CNTs Catalysts for Hydrodeoxygenation of Diphenyl Ether
Published on: August 17, 2019
Tuning ligand field strength with pendent Lewis acids: access to high spin iron hydrides
John J Kiernicki1, James P Shanahan1, Matthias Zeller2
1University of Michigan , 930 N. University , Ann Arbor , MI 48109 , USA .
Abstract:
Geometrically flexible 9-borabicyclo[3.3.1]nonyl units within the secondary coordination sphere enable isolation of high-spin Fe(ii)-dihydrides stabilized by boron-hydride interactions and a rare example of an isolable S = 3/2 reduction product. The borane-capped Fe(ii)-dihydride: (1) rapidly deprotonates E-H (E = N, O, P, S) bonds to afford borane-stabilized Fe adducts and (2) releases H2 upon exposure to π-acids. The Lewis acids provide an avenue for redox-leveling in analogy to the near constant operating potential for N2 reduction in nitrogenase.
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