Mitsunobu reagent [triphenylphosphine (TPP) and diethyl azodicarboxylate (DEAD)/diisopropyl azodicarboxylate (DIAD)]

Abstract

(A) Epoxides are obtained from acyclic 1,2-diols5a,b and cyclic trans-1,2-diols5c under the Mitsunobu conditions. 1,1-Disubstituted-1,2-diols lead to the formation of aldehydes or ketones.5d (B) Azidation of alcohols6a and α-hydroxy(alkyl)phosphonates6b can also be achieved under Mitsunobu conditions. (C) The Mitsunobu reaction can be used to distinguish between alcohol and phenol hydroxyls in esterification reactions.7 (D) Kinetic resolution of the racemic secondary alcohols8a can be effected by using the enantioselective Mitsunobu reaction of these alcohols with phthalimide in the presence of a chiral tri-coordinate phosphoramidite.8b (E) Single-step reductive deoxygenation of unhindered alcohols takes place under Mitsunobu conditions.9 (F) Intramolecular Mitsunobu reaction of 2-(hydroxyl iminomethyl) benzyl alcohols or 1,2-aminoalcohols gives benzoxazines10a or aziridines10b respectively.