dithioketal

A dithioketal is a functional group in organic chemistry characterized by a central carbon atom bonded to two sulfur atoms and two alkyl or aryl groups. It is the sulfur analog of a ketal, where oxygen atoms replace the sulfur atoms. Dithioketals are formed by the reaction of a ketone or aldehyde with a thiol, typically in the presence of an acid catalyst. Commonly, ethane-1,2-dithiol is used to form cyclic dithioketals. These compounds are generally stable under basic conditions but are readily cleaved under acidic conditions, regenerating the original carbonyl compound and the thiol. This lability in acid and stability in base makes dithioketals useful as protecting groups for carbonyls in organic synthesis. They can be selectively removed without affecting other acid-sensitive functional groups. Dithioketals also find application in certain chemical reactions as precursors to other sulfur-containing compounds or as ligands in coordination chemistry due to the soft nature of sulfur atoms.