In organic chemistry, a vinyl sulfone is a functional group consisting of a vinyl group bonded to a sulfone group. Specific compounds containing this functional group are divinyl sulfone, phenyl vinyl sulfone, methyl vinyl sulfone, and ethyl vinyl sulfone.
The sulfone makes the vinyl group electrophilic, allowing it to be used as a pharmacophore for binding to the thiol of cysteine residues. This same reactive nature is responsible for their major industrial use in vinyl sulfone dyes.