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In organosulfur chemistry, a sulfonyl group is either a functional group found primarily in sulfones, or a substituent obtained from a sulfonic acid by the removal of the hydroxyl group, similarly to acyl groups.[1]: 1470–1476
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.[1]: 53 [2]
Sulfonyl groups can be reduced to the sulfide with diisobutylaluminium hydride (DIBALH). Lithium aluminium hydride (LiAlH4) reduces some but not all sulfones to sulfides.[1]: 1851
In inorganic chemistry, when the group −S(=O)2− is not connected to any carbon atoms, it is referred to as sulfuryl.[3]
The names of sulfonyl groups typically end in -syl, such as:[1]: 497
| Group name | Full name | Pseudoelement symbol | Example |
|---|---|---|---|
| Tosyl | p-toluenesulfonyl | Ts | Tosyl chloride (p-toluenesulfonyl chloride) CH3C6H4SO2Cl |
| Brosyl | p-bromobenzenesulfonyl | Bs | |
| Nosyl | o- or p-nitrobenzenesulfonyl | Ns | |
| Mesyl | methanesulfonyl | Ms | Mesyl chloride (methanesulfonyl chloride) CH3SO2Cl |
| Triflyl | trifluoromethanesulfonyl | Tf | |
| Tresyl | 2,2,2-trifluoroethyl-1-sulfonyl | ||
| Dansyl | 5-(dimethylamino)naphthalene-1-sulfonyl | Ds | Dansyl chloride |