thioenolization

Thioenolization is a chemical reaction where a thioketone, a compound containing a carbon-sulfur double bond (C=S), transforms into an isomeric enethiol, which has a carbon-carbon double bond and a thiol (C-SH) group. This process is analogous to the enolization of carbonyl compounds (like ketones and aldehydes) to form enols.

For example, thioacetone (CH₃C(=S)CH₃) can undergo thioenolization to form 2-propenethiol (CH₃C(SH)=CH₂). Thioketones are generally highly reactive due to the poor overlap between the 2p orbitals of carbon and the 3p orbitals of sulfur in the C=S double bond. This reactivity makes them participate in reactions like Diels-Alder reactions and cycloadditions. While many thioketones are unstable, thioenolization offers a pathway to form more stable enethiol isomers.1