Tetracyanoethylene

Description

Tetracyanoethylene (TCNE) is a crystalline solid with a melting point of 200 °C. DuPont researchers prepared it?in 1957 by treating dibromomalononitrile?with copper in boiling benzene. TCNE is an excellent electron acceptor and has been used to prepare organic superconductors.
In 2001, J. S. Miller and co-workers at the University of Utah (Salt Lake City) discovered that the TCNE radical anion forms a dianionic dimer. They believed that the dimer contains an unusual four-atom, two-electron bond that connects the four olefinic carbon atoms. Recently, Miller and colleagues used Raman spectroscopy to confirm?the existence of the four-center bond.

Chemical properties

white to beige-brown crystalline powder, crystals. Tetracyanoethylene [670-54-2], ethenetetracarbonitrile, TCNE, ( NC)2C = C (CN)2, Mr 128.09, mp 197 – 198℃, bp 223℃, n25 D 1.560. The preferred synthetic preparation of TCNE involves the debromination of the KBr complex of dibromomalononitrile. Tetracyanoethylene is a reactive compound that undergoes a variety of reactions including addition, replacement and cyclization. The chemistry of TCNE is exhaustively reviewed in.

The Uses of Tetracyanoethylene

Used for postfunctional addition to polyphenylacetylene derivatives to change the oxygen permeability. As reactant for Regioselective [2+2] cycloaddition reaction for production of BODIPY dyes2 and TCBD derivatives, Thermal addition reaction with alkynes, One-pot reactions with nucleophilic reagents forming aromatic cyanovinyl compounds, Synthesis of cobalt tetracyanoethylene films, Biotransformation by Botrytis cinerea.

The Uses of Tetracyanoethylene

In the synthesis of spiro Compounds, in modified Diels-Alder reactions, as aromatizing agent: Longone, Smith, Tetrahedron Lett. 1962, 205.

The Uses of Tetracyanoethylene

Used for postfunctional addition to polyphenylacetylene derivatives to change the oxygen permeability

Reactant for:

• Regioselective [2+2] cycloaddition reaction for production of BODIPY dyes and TCBD derivatives
• Thermal addition reaction with alkynes
• One-pot reactions with nucleophilic reagents forming aromatic cyanovinyl compounds
• Synthesis of cobalt tetracyanoethylene films
• Biotransformation by Botrytis cinerea

What are the applications of Application

Tetracyanoethylene is Used for postfunctional addition to polyphenylacetylene derivatives to change the oxygen permeability

Definition

The first member of a class of compounds called cyanocarbons.

Synthesis Reference(s)

Organic Syntheses, Coll. Vol. 4, p. 877, 1963
The Journal of Organic Chemistry, 45, p. 5113, 1980 DOI: 10.1021/jo01313a019

Hazard

Hydrolyzes in moist air to hydrogen cyanide.

Purification Methods

Crystallise it from chlorobenzene, dichloroethane, or dichloromethane [Hall et al. J Org Chem 52 5528 1987]. Storeitat0oina desiccator over NaOH pellets. (It slowly evolves HCN on exposure to moist air CARE.) It can also be sublimed at 120o under vacuum. Also purify it by repeated sublimation at 120-130o/0.5mm. [Frey et al. J Am Chem Soc 107 748 1985, Traylor & Miksztal J Am Chem Soc 109 2778 1987, Fatiadi Synthesis 249 1986, Synthesis 749 1967, Beilstein 2 IV 1245.]