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Modification and Functionalization of the Guanidine Group by Tailor-made Precursors
Published on: April 27, 2017
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Group 6 Dihapto-Coordinate Dearomatization Agents for Organic Synthesis
Benjamin K Liebov1, W Dean Harman1
1Department of Chemistry, University of Virginia , Charlottesville, Virginia 22904, United States.
Chemical Reviews
|October 25, 2017
Summary
This review explores organic reactions of aromatic ligands coordinated to tungsten or molybdenum, focusing on C-C bond formation for novel organic synthesis. It highlights reactivity patterns and stereochemical outcomes for various aromatic substrates.
Area of Science:
- Organometallic Chemistry
- Organic Synthesis
Background:
- Aromatic ligands coordinated to transition metals offer unique reactivity for organic synthesis.
- Tungsten and molybdenum complexes have shown promise in activating aromatic systems.
Purpose of the Study:
- To review and analyze the organic reactions of aromatic ligands coordinated to tungsten or molybdenum from 2005-2017.
- To emphasize the utility of these reactions in synthesizing novel organic compounds.
Main Methods:
- Literature review of publications from 2005 to 2017.
- Analysis of C-C bond-forming reactions involving various organic building blocks.
- Examination of activated substrates including arenes, pyridines, pyrroles, and others.
Main Results:
- Elucidation of general reactivity patterns for η²-coordinated aromatic ligands.
- Identification of stereochemical preferences in these reactions.
- Comparison of reactivity with osmium, rhenium, and η⁶-arene complexes.
Conclusions:
- Tungsten and molybdenum complexes facilitate diverse C-C bond-forming reactions with various aromatic substrates.
- Understanding reactivity patterns and stereochemistry is key to their synthetic application.
- These metal-mediated reactions offer an alternative to other dearomatization strategies.
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