The Reaction of Phenylmethanesulfonyl Chloride With Tertiary Amines: Formation of Geometrical Isomers About a Carbon–sulfur Double Bond

In methylene chloride or ether solution, phenylmethanesulfonyl chloride reacts with triethylamine to give a mixture consisting primarily of trans-stilbene and cis diphenylethylene sulfone. In cyclohexane the same reagents yield principally a material which is shown to be a roughly 2:1 mixture of cis- and trans-oxythiobenzoyl chlorides (I and II, respectively). The latter compounds represent the first examples of geometrical isomerism about a double bond in which one of the atoms of the double bond is outside the first short period of the Periodic Table.