Sulfonamide (chemistry)

In chemistry, the sulfonamide functional group (also spelt sulphonamide ) is -S(=O)₂-NH₂, a sulfonyl group connected to an amine group.

A sulfonamide (compound) is a compound that contains this group. The general formula is RSO₂NH₂, where R is some organic group. For example, "methanesulfonamide" is CH₃SO₂NH₂. Any sulfonamide can be considered as derived from a sulfonic acid by replacing a hydroxyl group with an amine group.

In medicine, the term "sulfonamide" is sometimes used as a synonym for sulfa drug, a derivative or variation of sulfanilamide.

Organic synthesis

Sulfonamides can be prepared in the laboratory in many ways. For example:
* The reaction of sulfonyl chlorides with amines in the synthesis of sulfonylmethylamide [Organic Syntheses, Coll. Vol. 4, p.943 (1963); Vol. 34, p.96 (1954). [http://www.orgsynth.org/orgsyn/prep.asp?prep=cv4p0943 Online Article] ] . A readily available sulfonyl chloride source is tosyl chloride [Organic Syntheses, Coll. Vol. 5, p.39 (1973); Vol. 48, p.8 (1968). [http://www.orgsynth.org/orgsyn/prep.asp?prep=cv5p0039 Online Article] ] .
* Symmetric sulfonamides are prepared directly from amines and sulfur dioxide gas ["Sulfamides and sulfamide polymers directly from sulfur dioxide" Alexander V. Leontiev, H. V. Rasika Dias and Dmitry M. Rudkevich Chem. Commun., 2006, 2887 - 2889, DOI|10.1039/b605063h] : :

In this example, the reactants are aniline, triethylamine, and iodine. Sulfur dioxide is believed to be activated through a series of intermediates: Et₃N-I⁺-I^-, Et₃N-I⁺-I₃^- and Et₃N⁺-SO₂^-.

ee also

* Sulfonamide (medicine)
* Sulfamic acid
* Sulfamide

References