Sulfur diimide


Sulfur diimides are chemical compounds of the formula S2. The parent member, S2, is of only theoretical interest. Other derivatives where R is an organic group are stable and useful reagents.

Organic derivatives

A particularly stable derivative is di-t-butylsulfurdiimide. A yellow oil, it is prepared by reaction of tert-butylamine with sulfur dichloride to give the intermediate "S", which decomposes at 60 °C to give the diimide. Other routes to sulfur diimides involve treatment of sulfur tetrafluoride with amines. A third route involves transimidation of disulfonylsulfodiimide:
N,N-Bissulfur diimide is obtained from methylcarbamate.

Structure, bonding, reactions

These compounds are related to SO2. They have planar SN2C2 cores, although both syn and anti isomers are observed.
Sulfur diimides are electrophilic. They undergo Diels-Alder reaction with dienes. Organolithium compounds add to give the corresponding anions:
The triimido analogues of sulfite can be generated by treating the sulfur diimides with amide: