Tosylate

Tosylate Definition:

An excellent leaving group (OTs).

Tosylate Explained:

Useful because alcohols are poor leaving groups in SN2 reactions, in comparison to the tosylate group. It is the alteration of alkyl alcohols to alkyl tosylates that allows an SN2 reaction to happen in the presence of good nucleophile. A tosyl group can function as a protecting group in organic synthesis.