Sulfonyl
A sulfonyl group can refer either to a functional group found primarily in sulfones or to a substituent obtained from a sulfonic acid by the removal of the hydroxyl group similarly to acyl groups. Sulfonyl groups can be written as having the general formula R-S(=O)2-R', where there are two double bonds between the sulfur and oxygen.
Sulfonyl groups can be reduced to the hydrocarbon with lithium aluminium hydride (LiAlH4).
In inorganic chemistry, when the group -S(=O)2- is not connected to any carbon atoms, it is referred to as sulfuryl.
The names of sulfonyl groups typically end in -syl, such as:
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