Thiirane, more commonly known as ethylene sulfide, is the cyclic

chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...

with the formula C₂H₄S. It is the smallest sulfur-containing heterocycle and the simplest episulfide. Like many organosulfur compounds, this species has a highly unpleasant odour. Thiirane is also used to describe any derivative of the parent ethylene sulfide.

Structure and properties

According to electron diffraction, the C-C and C-S distances in ethylene sulfide are respectively 1.473 and 1.811 Å. The C-C-S and C-S-C angles are respectively 66.0 and 48.0°. The microwave and infrared spectra were studied experimentally and computationally.

Preparation and reactions

It can be prepared by the reaction of ethylene carbonate and KSCN. For this purpose the KSCN is first melted under vacuum to remove water. :KSCN + C₂H₄O₂CO → KOCN + C₂H₄S + CO₂ Ethylenesulfide adds to amines to afford 2-mercaptoethylamines, which are good chelating ligands. :C₂H₄S + R₂NH → R₂NCH₂CH₂SH This process is often called mercaptoethylation. Oxidation of thiirane with periodate gives ethylene episulfoxide.

References

{{sulfur compounds Episulfides