Dithiazolium

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Dithiazolium refers to families of heterocycles consisting of C2NS2 rings. The cations are aromatic on the grounds that they have six pi-electrons. In principle, several isomers are possible, depending on the relative location of the C, N, and S atoms in the ring.

1,2,5-Dithiazolium cations arise from cycloaddition of dithionitronium (NS2+) to alkynes. [1] The derivative with two trifluoromethyl groups (prepared from hexafluorobutyne) can be reduced to the 7 electron radical. This particular 1,3,5-dithiazole is also rare example of a radical that can be obtained as a solid, liquid, and gas. The gas is blue. [2]

Appel's salt is an example of a 1,2,3-dithiazolium. [3]

Related Research Articles

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2
H
6
. At standard temperature and pressure, ethane is a colorless, odorless gas. Like many hydrocarbons, ethane is isolated on an industrial scale from natural gas and as a petrochemical by-product of petroleum refining. Its chief use is as feedstock for ethylene production.

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4
H
6
. It is a neutral free molecule with two unsatisfied valence bonds, and is therefore a highly reactive free radical. Formally, it can be viewed as an isobutylene molecule C
4
H
8
with two hydrogen atoms removed from the terminal methyl groups.

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References

  1. MacLean, Gregory K.; Passmore, Jack; Rao, M. N. Sudheedra; Schriver, Melbourne J.; White, Peter S.; Bethell, Donald; Pilkington, Roger S.; Sutcliffe, Leslie H. (1985). "Preparation of 1,3,2-Dithiazolium Hexafluoroarsenate(V), Preparation and Crystal Structures of 5-Methyl-1,3,2,4-dithiadiazolium and 4-Methyl-1,3,2-dithiazolium Hexafluoroarsenate(V) and the Reduction of These Salts to Stable Free Radicals". Journal of the Chemical Society, Dalton Transactions (7): 1405. doi:10.1039/dt9850001405.
  2. Brownridge, Scott; Du, Hongbin; Fairhurst, Shirley A.; Haddon, Robert C.; Oberhammer, Heinz; Parsons, Simon; Passmore, Jack; Schriver, Melbourne J.; Sutcliffe, Leslie H.; Westwood, Nicholas P. C. (2000). "The Isolation, Characterisation, Gas Phase Electron Diffraction and Crystal Structure of the Thermally Stable Radical CF3CSNSCCF3". Journal of the Chemical Society, Dalton Transactions (19): 3365–3382. doi:10.1039/B001489N.
  3. Rees, Charles W. (May 1992). "Polysulfur-nitrogen heterocyclic chemistry". Journal of Heterocyclic Chemistry. 29 (3): 639–651. doi:10.1002/jhet.5570290306.