Visible-Light-Mediated Oxidative Debenzylation Enables the Use of Benzyl Ethers as Temporary Protecting Groups
Cristian Cavedon, Eric T. Sletten, Amiera Madani, Olaf Niemeyer, Peter H. Seeberger, Bartholomäus Pieber
Abstract
The cleavage of benzyl ethers by catalytic hydrogenolysis or Birch reduction suffers from poor functional group compatibility and limits their use as a protecting group. The visible-light-mediated debenzylation disclosed here renders benzyl ethers temporary protective groups, enabling new orthogonal protection strategies. Using 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) as a stoichiometric or catalytic photooxidant, benzyl ethers can be cleaved in the presence of azides, alkenes, and alkynes. The reaction time can be reduced from hours to minutes in continuous flow.
Topics & Concepts
ChemistryHydrogenolysisCatalysisProtecting groupOxidative cleavageStoichiometryBenzyl alcoholOxidative phosphorylationOrganic chemistryCombinatorial chemistryPhotochemistryBiochemistryAlkylRadical Photochemical ReactionsInnovative Microfluidic and Catalytic Techniques InnovationOxidative Organic Chemistry Reactions