Thioketone

Thioketones are organic compounds related to conventional ketones. Instead of the formula R2C=O, thioketones, or thiones as they are also called, have the formula R2C=S. Unhindered thioketones are typically unstable; such compounds tend to form polymers or rings.

Preparative methods
One approach to generating thiocarbonyl-molecules entails treating a ketone with Lawesson's reagent. Other methods use of an hydrogen chloride with hydrogen sulfide. Bis(trimethylsilyl)sulfide has also been employed.

Thiobenzophenone, the prototype
Thiobenzophenone, (C6H5)2CS, is quite stable. This deep blue compound dissolves readily in organic solvents. It photooxidizes in air to benzophenone and sulfur. Since the discovery of thiobenzophenone, a variety of related thiones have been prepared by the Tokitoh group.

Selenones
The selenium versions of the thioketones are less stable than thiones. Selenobenzophenone reversibly dimerizes. It is known to react with 1,3-dienes in a Diels-Alder reaction.

Weblinks
Definition of Thioketones in the IUPAC Golden Book

Thioketone チオケトン