Thiol oxidation to disulfides

Thiol oxidation to disulfides Definition:

When thiols treated with an oxidizing agent such as iodine or molecular oxygen, thiols can be converted to disulfides.

Thiol oxidizing to disulfides Explained:

Thiols easily undergo oxidation to produce disulfides. In more careful oxidation with bromine, disulfides, analogues of sulfur peroxide are formed. This conversation requires an oxidizing reagent, such as bromine in aqueous hydroxide.

STEP 1. Deprotonation of the thiol to generate a thiolate ion by a strong base such as hydroxide.

STEP 2. Thiolate ion, obtained in the previous step, is an excellent nucleophile and can attack molecular bromine in the first SN2 process. And in the second SN2 process, another thiolate functions as a nucleophile to produce disulfide.

Many other oxidizing agents can also be used for conversation of thiols into disulfides. And catalysts can be used to speed up the process.

Disulfides are also easily reduced back to thiols when treated with a reducing agent, such as alkali metals.