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Preparation of 6-aminocyclohepta-2,4-dien-1-one Derivatives via Tricarbonyl(tropone)iron
Published on: August 12, 2019
The search for tricyanomethane (cyanoform)
Dubravka Sisak1, Lynne B McCusker, Andreas Buckl
1Laboratory of Crystallography, ETH Zürich, Hönggerberg, HCI, 8093 Zurich, Switzerland.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|May 19, 2010
Summary
Tricyanomethane, a strong carbon acid, has long resisted isolation. This study identifies several stable derivatives, including hydronium tricyanomethanide and iminoacrylimide, advancing the understanding of this elusive compound.
Area of Science:
- Organic Chemistry
- Chemical Synthesis
- Computational Chemistry
Background:
- Tricyanomethane (cyanoform) is recognized as a potent carbon acid.
- Despite extensive efforts over a century, tricyanomethane has not been successfully isolated or characterized in stable forms.
- Previous identification was limited to vapor-phase microwave spectroscopy at low pressures.
Purpose of the Study:
- To review and replicate preparative methods for tricyanomethane.
- To identify and characterize stable derivatives of tricyanomethane.
- To computationally assess the relative energies of key molecular species.
Main Methods:
- Review and partial replication of preparative chemistry.
- Spectroscopic methods (e.g., microwave, IR, NMR - implied).
- Diffraction methods, including powder diffraction.
- Quantum-mechanical calculations (MP2/6-311++g(2d,2p)).
Main Results:
- Identification of hydronium tricyanomethanide (3).
- Characterization of (Z)-3-amino-2-cyano-3-iminoacrylimide (4).
- Isolation of a co-crystal of 4 with sulfuric acid and an addition product of the dicyanoketenimine tautomer 2 with HCl (5/6).
Conclusions:
- Stable derivatives of tricyanomethane have been successfully prepared and characterized.
- These findings provide insights into the chemistry of this historically elusive compound.
- Computational analysis supports the understanding of the energetics of related species.
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