Dithietane

Dithietanes are saturated heterocyclic compounds that contain two divalent sulfur atoms and two sp³-hybridized carbon centers. Two isomers are possible for this class of organosulfur compounds:

A stable 1,2-dithietane derivative is trans-3,4-diethyl-1,2-dithietane 1,1-dioxide, formed by the spontaneous dimerization of the lachrymatory agent syn-propanethial-S-oxide, found in onion.

Oxidized forms of 1,3-dithietane are well known, although they are often not prepared from the dithietane. Examples include the so-called zwiebelanes (2,3-dimethyl-5,6-dithiabicyclo[2.1.1]hexane S-oxides) from onion volatiles and 1,3-dithietane 1,1,3,3-tetraoxide, the so-called sulfene dimer.

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