Photoinduced Deoxygenative Boration of Unactivated Alcohols Involving In-Situ-Formed Alkyl Iodides
Xiaojie Liu1, Biping Xu1, Martin Oestreich1
1Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623 Berlin, Germany.
Abstract:
A method for the direct two-step/one-pot conversion of unactivated 1°, 2°, and 3° alcohols into the corresponding alkylboronate esters is reported. The hydroxy group is activated in situ by reaction with the Hendrickson "POP" reagent. The rapidly formed alkoxyphosphonium salt is then reacted with bis(catecholato)diboron under visible-light irradiation in the presence of stoichiometric amounts of lithium iodide. This one-pot protocol streamlines the two-step procedure, and it is operationally simple and scalable. The functional-group tolerance is broad.
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