Tetraiodoethylene, TIE or diiodoform, is an organoiodine compound with the

chemical formula A chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as pare ...

. Its structure is . It is an odourless yellow crystalline solid that is soluble in

benzene Benzene is an Organic compound, organic chemical compound with the Chemical formula#Molecular formula, molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar hexagonal Ring (chemistry), ring with one hyd ...

and

chloroform Chloroform, or trichloromethane (often abbreviated as TCM), is an organochloride with the formula and a common solvent. It is a volatile, colorless, sweet-smelling, dense liquid produced on a large scale as a precursor to refrigerants and po ...

, and insoluble in water.Lide, D. R. (1995). CRC Handbook of Chemistry and Physics. (Special Student Edition): A Ready-Reference Book of Chemical and Physical Data. CRC-Press. Page 522 It has been used as an

antiseptic An antiseptic ( and ) is an antimicrobial substance or compound that is applied to living tissue to reduce the possibility of sepsis, infection, or putrefaction. Antiseptics are generally distinguished from ''antibiotics'' by the latter's abil ...

and a component in

pesticide Pesticides are substances that are used to control pests. They include herbicides, insecticides, nematicides, fungicides, and many others (see table). The most common of these are herbicides, which account for approximately 50% of all p ...

and

fungicide Fungicides are pesticides used to kill parasitic fungi or their spores. Fungi can cause serious damage in agriculture, resulting in losses of yield and quality. Fungicides are used both in agriculture and to fight fungal infections in animals, ...

formulations. It is the periodinated analogue of

ethylene Ethylene (IUPAC name: ethene) is a hydrocarbon which has the formula or . It is a colourless, flammable gas with a faint "sweet and musky" odour when pure. It is the simplest alkene (a hydrocarbon with carbon–carbon bond, carbon–carbon doub ...

. It is a decomposition product of

carbon tetraiodide Carbon tetraiodide is a tetrahalomethane with the molecular formula . Being bright red, it is a relatively rare example of a highly colored methane derivative (chemistry), derivative. It is only 2.3% by weight carbon, although other methane derivat ...

and

diiodoacetylene Diiodoacetylene is the organoiodine compound with the formula . It is a white, volatile solid that dissolves in organic solvents. It is prepared by iodination of trimethylsilylacetylene. Although samples explode above 80 °C, diiodoacetylene i ...

.''Peculiar Decomposition of Diiodoacetylene'', Victor Meyel and Wilhelm Pemsel (1896) Tetraiodoethylene reacts with

ethylamine Ethylamine, also known as ethanamine, is an organic compound with the chemical formula, formula CH3CH2NH2. This colourless gas has a strong ammonia-like odor. It condenses just below room temperature to a liquid miscibility, miscible with virtual ...

to give ethylamine di-tetraiodoethylene, , and ethylamine tetraiodoethylene, . Tetraiodoethylene and

iodine pentafluoride Iodine pentafluoride is an interhalogen compound with chemical formula IF5. It is one of the fluorides of iodine. It is a colorless liquid, although impure samples appear yellow. It is used as a fluorination reagent and even a solvent in speci ...

yield

iodopentafluoroethane Pentafluoroethyl iodide is a suggested component of a fire-extinguishing composition.US patent application 20010048094 It is a very dense gas. Production Pentafluoroethyl iodide can be produced by electrochemical fluorination of 1,1,2,2-tetrafl ...

.Journal of the Chemical Society. (1948). page 2188 Tetraiodoethylene turns brown and emits a characteristic odour due to decomposition when exposed to light.

History

Tetraiodoethylene was discovered by

Baeyer Johann Friedrich Wilhelm Adolf von Baeyer (; 31 October 1835 – 20 August 1917) was a German chemist who synthesised indigo and developed a nomenclature for cyclic compounds (that was subsequently extended and adopted as part of the IUPAC org ...

in 1885. It was proposed as an

under the name Diiodoform, in 1893 by M. L. Maquenne and Taine. It was an alternative to

iodoform Iodoform (also known as triiodomethane) is the organoiodine compound with the chemical formula . It is a pale yellow, crystalline, volatile substance, with a penetrating and distinctive odor (in older chemistry texts, the smell is sometimes refe ...

''New Remedies – Diiodoform'' in Merck's Market Report and Pharmaceutical Journal: An Independent Monthly Magazine Devoted to the Professional and Commercial Interests of the Druggist. (1894). which has a strong and persistent odour that caused difficulties for physicians in private practices.''Selections – DIIODOFORM'' in The International Dental Journal. (1895). USA: International Dental Publication Company.

Synthesis

Tetraiodoethylene can be made by the

iodination In chemistry, halogenation is a chemical reaction which introduces one or more halogens into a chemical compound. Halide-containing compounds are pervasive, making this type of transformation important, e.g. in the production of polymers, drugs. ...

calcium carbide Calcium carbide, also known as calcium acetylide, is a chemical compound with the chemical formula of . Its main use industrially is in the production of acetylene and calcium cyanamide. The pure material is colorless, while pieces of technica ...

:''TETRA-IODO-ETHYLENE'', The Pharmaceutical Era. (1897). USA, D. O. Haynes & Company. :

Diiodoacetylene Diiodoacetylene is the organoiodine compound with the formula . It is a white, volatile solid that dissolves in organic solvents. It is prepared by iodination of trimethylsilylacetylene. Although samples explode above 80 °C, diiodoacetylene i ...

is a byproduct of the reaction which can later be iodinated to TIE. The action of aqueous solution of

potassium hydroxide Potassium hydroxide is an inorganic compound with the formula K OH, and is commonly called caustic potash. Along with sodium hydroxide (NaOH), KOH is a prototypical strong base. It has many industrial and niche applications, most of which utili ...

and

iodine Iodine is a chemical element; it has symbol I and atomic number 53. The heaviest of the stable halogens, it exists at standard conditions as a semi-lustrous, non-metallic solid that melts to form a deep violet liquid at , and boils to a vi ...

barium carbide Barium carbide (also referred to as barium ethynediide or barium acetylide) is a chemical compound in the carbide family having the chemical formula . It consists of barium cations and acetylide anions . Preparation Barium carbide can be synthes ...

can also give TIE. Another synthesis involves mixing separate solutions of diiodoacetylene and

carbon disulphide Carbon disulfide (also spelled as carbon disulphide) is an inorganic compound with the chemical formula and structure . It is also considered as the anhydride of thiocarbonic acid. It is a colorless, flammable, neurotoxic liquid that is used as ...

. Tetraiodoethylene would be left as a residue after carbon disulphide was evaporated.

References

{{Reflist Iodoalkenes Pesticides Fungicides Antiseptics

History

Synthesis

See also

References