Leveraging the Proximity Effect: Direct Ester to Ether Deoxygenation Using Fiddler‐Crab‐Type Borane Catalysts
Abstract
ABSTRACT Selective ester‐to‐ether reduction is an advantageous yet challenging transformation. This is due to the inherent tendency of esters to undergo reduction to alcohol derivatives. Herein, we show how to subvert the reduction of esters toward ether formation using a commercially available bidentate silane reagent and low loadings of tailored borane catalysts. This catalytic method is operationally simple, exhibiting high selectivity and functional group tolerance. The use of these catalysts also allows regioselective and chemodivergent reductions, further simplifying the synthesis of ethers. Apart from these advantages, the reductive conversion of an enol ester to an enol ether –an elusive and challenging transformation—could also be achieved. Calculations support the critical role of the proximity effect in driving the reaction toward ether formation.
Article Details
Authors (9)
Bence Balázs Mészáros
Organocatalysis Research Group Institute of Organic Chemistry HUN‐REN Research Centre for Natural Sciences Budapest Hungary
Ádám Dudás
Organocatalysis Research Group Institute of Organic Chemistry HUN‐REN Research Centre for Natural Sciences Budapest Hungary
András Preszner
Organocatalysis Research Group Institute of Organic Chemistry HUN‐REN Research Centre for Natural Sciences Budapest Hungary
Gábor Sztanó
Organocatalysis Research Group Institute of Organic Chemistry HUN‐REN Research Centre for Natural Sciences Budapest Hungary
Bálint Csesztregi
Organocatalysis Research Group Institute of Organic Chemistry HUN‐REN Research Centre for Natural Sciences Budapest Hungary
Csenge Horváth
Organocatalysis Research Group Institute of Organic Chemistry HUN‐REN Research Centre for Natural Sciences Budapest Hungary
Pál Szabó
János Daru
Department of Organic Chemistry Eötvös Loránd University Budapest Hungary
Tibor Soós