title: Enantioselective halogenative semi-pinacol rearrangement: extension of substrate scope and mechanistic investigations.
abstract: The present Full Paper article discloses a survey of our recent results obtained in the context of the enantioselective halogenation-initiated semi-pinacol rearrangement. Commencing with the fluorination/semi-pinacol reaction first and moving to the heavier halogens (bromine and iodine) second, the scope and limitations of the halogenative phase-transfer methodology will be discussed and compared. An extension of the fluorination/semi-pinacol reaction to the ring-expansion of five-membered allylic cyclopentanols will be also described, as well as some preliminary results on substrates prone to desymmetrization will be given. Finally, the present manuscript will culminate with a detailed mechanistic investigation of the canonical fluorination/semi-pinacol reaction. Our mechanistic discussion will be based on in situ reaction progress monitoring, complemented with substituent effect, kinetic isotopic effect and non-linear behaviour studies.
authors.affiliation: Department of Organic Chemistry, University of Geneva, Quai Ernest Ansermet 30, 1211 Geneva 4 (Switzerland).
authors.forename: Fedor
authors.initials: F
authors.lastname: Romanov-Michailidis
authors.forename: Maria
authors.initials: M
authors.lastname: Romanova-Michaelides
authors.forename: Marion
authors.initials: M
authors.lastname: Pupier
authors.forename: Alexandre
authors.initials: A
authors.lastname: Alexakis
keywords: halogenation; kinetic isotopic effect; linear free-energy relationship; reaction kinetics; semi-pinacol rearrangement