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The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Ring-borylated 15-electron and 17-electron ansa-chromocene complexes, their physical properties and molecular
Pamela J Shapiro1, Piet-Jan Sinnema, Philippe Perrotin
1Department of Chemistry, University of Idaho, Moscow, Idaho 83844-2343, USA. shapiro@uidaho.edu
Chemistry (Weinheim an Der Bergstrasse, Germany)
|May 17, 2007
Summary
This study details the thermal decomposition of a zwitterionic, ring-borylated ansa-chromocene complex. The decomposition yields new chromium complexes with altered electronic properties, offering insights into organometallic chemistry.
Area of Science:
- Organometallic Chemistry
- Coordination Chemistry
- Boron Chemistry
Background:
- Ansa-chromocene complexes are versatile organometallic compounds.
- Zwitterionic and borylated complexes present unique reactivity and electronic properties.
- Understanding thermal decomposition pathways is crucial for synthetic applications.
Purpose of the Study:
- To investigate the thermal decomposition of a specific zwitterionic, ring-borylated ansa-chromocene hydrido carbonyl complex.
- To characterize the resulting decomposition products and their electronic structures.
- To explore the influence of borylation on the redox properties of these chromium complexes.
Main Methods:
- Synthesis of the precursor complex [Cr(CO)H{Me(4)C(2)(C(5)H(4))[C(5)H(3)B(C(6)F(5))(3)]}] (2).
- Thermal decomposition studies in toluene at various temperatures.
- Characterization of products using X-ray crystallography, cyclic voltammetry, DFT calculations, EPR, and 19F NMR spectroscopy.
Main Results:
- Complex 2 decomposes above -25°C to a mixture of Cr(III) complexes.
- Carbon monoxide elimination from a Cr(III) intermediate generates a 15-electron Cr complex (3a).
- X-ray structures of several complexes (3b-e, 5) were determined, revealing structural details.
- Redox potentials of borylated complexes are significantly reduced due to electrostatic stabilization by the borylate group.
Conclusions:
- The thermal decomposition pathway of the zwitterionic, ring-borylated ansa-chromocene complex is elucidated.
- Borylation dramatically influences the electronic and redox properties of the resulting chromium complexes.
- Spectroscopic and computational methods provide detailed characterization and mechanistic insights.
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