Pt-catalyzed C-C activation induced by C-H activation
Miriam A Bowring1, Robert G Bergman, T Don Tilley
1Department of Chemistry, University of California, and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
Journal of the American Chemical Society
|August 22, 2013
Summary
Platinum(II) catalysts cleave two carbon-carbon bonds in a hydrocarbon, leading to a novel rearrangement product. This study reveals an unusual catalytic mechanism initiated by C-H bond activation.
Area of Science:
- Organometallic Chemistry
- Catalysis
- Organic Synthesis
Background:
- Carbon-carbon (C-C) bond cleavage is a fundamental transformation in organic chemistry.
- Developing efficient catalytic methods for C-C bond activation remains a significant challenge.
Purpose of the Study:
- To investigate the catalytic cleavage of two C-C single bonds in spiro[bicyclo[2.2.1]hept-2-ene-7,1'-cyclopropane].
- To elucidate the mechanism of this novel catalytic transformation using platinum(II) catalysts.
Main Methods:
- Treatment of the hydrocarbon substrate with platinum(II) catalysts, specifically (Me2bpy)PtPh(NTf2).
- Characterization of the product using NMR spectroscopy and electrospray ionization mass spectrometry.
- Mechanistic studies involving deuterium labeling and density functional theory (DFT) calculations.
Main Results:
- The catalytic reaction successfully cleaved two C-C single bonds in the substrate.
- A surprising rearrangement product, 1,2,4,7,7a-pentahydroindene, was obtained in good yield.
- Evidence supports an unusual catalytic mechanism involving initial C-H bond activation followed by C-C bond cleavage.
Conclusions:
- Platinum(II) catalysts can effectively mediate the cleavage of multiple C-C bonds in a complex hydrocarbon.
- The reaction proceeds through a unique mechanism initiated by C-H bond activation, offering new insights into catalytic C-C bond activation strategies.
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