Dithiolium salt

Dithiolium salts are compounds of the formula [(RC)3S2]+X− (R = H, alkyl, aryl, etc.).

These salts consist of a planar organic cation with a variety of anions such as halides.

These cations differ with respect to the relative positions of the pair of sulfur atoms.

Both isomers feature a planar ring, which is aromatic owing to the presence of 6π electrons.

[1] For example, the 1,2-ditholium ring can be represented as an allyl cation of the three carbons,[2] with each sulfur atom donating one of its lone pairs of electrons to give a total of three pairs.

1,2- and 1,3-dithiolium cations.
Structure of diphenyl-1,2-dithiolium cation (as its bisulfate salt). Selected distances: S-S = 2.019(5); S-C=173(1); C ring -C ring = 1.38(1) Å. [ 3 ]