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Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
8.3K
Subporphyrinato boron(III) hydrides
Eiji Tsurumaki1, Jooyoung Sung, Dongho Kim
1Department of Chemistry, Graduate School of Science, Kyoto University , Sakyo-ku, Kyoto 606-8502, Japan.
Journal of the American Chemical Society
|January 8, 2015
Summary
New subporphyrinato boron(III) hydrides were synthesized and characterized. These compounds exhibit unique B-H bond characteristics and act as effective reducing agents in organic synthesis.
Area of Science:
- Organometallic Chemistry
- Supramolecular Chemistry
- Synthetic Chemistry
Background:
- Subporphyrins are macrocyclic compounds with unique electronic and steric properties.
- Boron(III) complexes offer diverse reactivity and coordination possibilities.
- Development of novel reducing agents is crucial for synthetic organic chemistry.
Purpose of the Study:
- To synthesize and characterize novel subporphyrinato boron(III) hydrides.
- To investigate the structural and spectroscopic properties of the B-H bond.
- To evaluate the reducing capabilities of these new boron compounds.
Main Methods:
- Reduction of subporphyrinato boron(III) methoxides using diisobutylaluminum hydride (DIBAL-H).
- Spectroscopic characterization including 1H NMR, 11B NMR, and IR spectroscopy.
- Single crystal X-ray diffraction analysis for structural elucidation.
- Reactivity studies involving reactions with water, HCl, aldehydes, and imines.
Main Results:
- Successful synthesis of subporphyrinato boron(III) hydrides in good yields.
- Unambiguous confirmation of the B-H bond through NMR, IR, and X-ray diffraction.
- Observed red shifts in absorption and fluorescence spectra attributed to the electron-donating B-hydride.
- Demonstrated hydridic character via H2 evolution and successful reduction of aldehydes and imines.
Conclusions:
- Subporphyrinato boron(III) hydrides represent a new class of organoboron compounds.
- The B-H bond in these complexes exhibits distinct spectroscopic and structural features.
- These compounds show potential as versatile reducing agents in organic synthesis.
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