Sulfinamide
In organosulfur chemistry, sulfinamide is a functional group with the structure . This functionality is composed of a sulfur-carbon single bond, a sulfur-nitrogen single bond, and a sulfur-oxygen bond. As a non-bonding electron pair is present on the sulfur, the sulfur atom is a stable stereogenic centre, and so these compounds are chiral. They are sometimes referred to as S-chiral sulfinamides. Sulfinamides are amides of sulfinic acid.
Structure
Sulfinamides do not undergo inversion. They can therefore be synthesised and/or isolated in enantiopure forms. This has led to their use as chiral ammonia equivalents. Chiral sulfinamides such as tert-butanesulfinamide, p-toluenesulfinamide and 2,4,6-trimethylbenzenesulfinamide are all chiral auxiliaries.Synthesis
Sulfinamides are traditionally produced by the reaction of sulfinyl chlorides with primary or secondary amines. They also arise by the addition of Grignard reagents to sulfinylamines, followed by protonation:Yet another route entails peracid-oxidation of sulfenylphthalimides, which gives sulfinylphthalimides.
Examples
A common sulfinamide is tert-butanesulfinamide, p-toluenesulfinamide, and mesitylSulfinamides arise in nature by the addition of nitroxyl to thiols: