Thioketone

In organic chemistry, thioketones (from Ancient Greek θεῖον (theion) 'sulfur';[1] also known as thiones or thiocarbonyls) are organosulfur compounds related to conventional ketones in which the oxygen has been replaced by a sulfur.

[6] Consistent with the double bond rule, most alkyl thioketones are unstable with respect to dimerization.

[5] The striking blue appearance of thiobenzophenone is attributed to π→ π* transitions upon the absorption of red light.

There are no general methods to oxidize methylene groups to thioketones,[10]: 929–930  reflecting sulfur's comparable electronegativity to carbon.

Thiobenzophenone [(C6H5)2CS] is a stable deep blue compound that dissolves readily in organic solvents.

General formula of a thioketone
Solution and solid samples of thiobenzophenone. The blue color is consistent with a small HOMO–LUMO gap associated with the thiocarbonyl functional group.