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Preparation of Carbon Nanosheets at Room Temperature
Published on: March 8, 2016
Synthesis and structure of a hexacoordinate carbon compound
Torahiko Yamaguchi1, Yohsuke Yamamoto, Daisuke Kinoshita
1Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan.
Journal of the American Chemical Society
|May 8, 2008
Summary
Researchers explored six coordination and hypervalence in carbon compounds. Steric constraints enabled four ether oxygen atoms to approach an allenic carbon, confirming hexacoordinate carbon in a dimethylated dication.
Area of Science:
- Organometallic Chemistry
- Computational Chemistry
- Structural Chemistry
Background:
- Carbon compounds typically exhibit four-coordinate bonding.
- Hypervalence in carbon, where it exceeds the octet rule, is a rare phenomenon.
- Steric hindrance can influence molecular geometry and coordination numbers.
Purpose of the Study:
- To investigate the possibility of achieving six-coordinate carbon.
- To explore the concept of hypervalence in carbon compounds.
- To synthesize and characterize novel carbon complexes with unusual coordination.
Main Methods:
- Utilized steric constraints to position multiple donor atoms around a central carbon.
- Employed experimental charge density analysis to determine bonding characteristics.
- Performed Density Functional Theory (DFT) calculations to support experimental findings.
Main Results:
- Successfully brought four ether oxygen atoms into close proximity to an allenic carbon.
- Confirmed the formation of a hexacoordinate carbon center in the dimethylated dication 2.
- Charge density analysis and DFT calculations provided strong evidence for the unusual coordination.
Conclusions:
- The study provides compelling evidence for hexacoordinate carbon, challenging traditional bonding models.
- The synthesized dication is arguably hypervalent, expanding the known scope of carbon's bonding capabilities.
- This work opens new avenues for exploring hypercoordinate and hypervalent species in chemistry.
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