Friedel–Crafts Benzylation of Activated and Deactivated Arenes†
Gabriel Schäfer
Laboratorium für Organische Chemie, Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology (ETH) Zürich, Wolfgang Pauli Strasse 10, 8093 Zürich (Switzerland) http://www.bodegroup.org
Search for more papers by this authorCorresponding Author
Prof. Dr. Jeffrey W. Bode
Laboratorium für Organische Chemie, Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology (ETH) Zürich, Wolfgang Pauli Strasse 10, 8093 Zürich (Switzerland) http://www.bodegroup.org
Laboratorium für Organische Chemie, Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology (ETH) Zürich, Wolfgang Pauli Strasse 10, 8093 Zürich (Switzerland) http://www.bodegroup.orgSearch for more papers by this authorGabriel Schäfer
Laboratorium für Organische Chemie, Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology (ETH) Zürich, Wolfgang Pauli Strasse 10, 8093 Zürich (Switzerland) http://www.bodegroup.org
Search for more papers by this authorCorresponding Author
Prof. Dr. Jeffrey W. Bode
Laboratorium für Organische Chemie, Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology (ETH) Zürich, Wolfgang Pauli Strasse 10, 8093 Zürich (Switzerland) http://www.bodegroup.org
Laboratorium für Organische Chemie, Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology (ETH) Zürich, Wolfgang Pauli Strasse 10, 8093 Zürich (Switzerland) http://www.bodegroup.orgSearch for more papers by this authorThis work was supported by ETH Research Grant ETH-12 11-1. We thank the ETH Zürich Mass Spectrometry Service for spectroscopic data, Aaron Dumas for helpful discussions, and Cam-Van Thi Vo for a preliminary study.
Graphical Abstract
NO going back makes possible facile Friedel–Crafts benzylations with moderate reaction temperatures, simple reaction workups, and improved substrate scope for the formation of synthetically important diarylmethanes (see scheme). Upon complexation with BF3⋅OEt2, hydroxamates serve as reversible leaving groups that stabilize highly reactive carbocations. Even deactivated arenes and electron-deficient benzylhydroxamates react cleanly under these conditions.
Supporting Information
Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors.
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| anie_201105380_sm_miscellaneous_information.pdf3.3 MB | miscellaneous_information |
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