Facile Access to Chelating CAArC‐Phosphine (CAArCPhos) Palladium Complexes
Abstract
Abstract In this article, we present a synthetic route to 4‐(diphenyl‐phosphino) isoindolium salts based on a new protecting group strategy. Key to success is the use of hemi‐aminal methyl ether precursors, which serve as base‐stable iminium salt equivalents that enable halogen‐metal exchange and subsequent functionalization. After removal of the protecting group, the catalytically active palladium(II) complexes are formed of phosphine isoindolium salts by a CMD‐like metalation process, producing the first examples of chelating cyclic amino(aryl) carbene complexes. Calculations on the mechanism support an acetate‐assisted intramolecular palladation of the cyclic amino(aryl) carbene‐phosphine (CAArCPhos) ligand enabled by the phosphine directing group through a six‐membered transition state.
Article Details
Authors (9)
K. Georg Leistikow
Organisch‐Chemisches Institut Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
Alexander Wingelstern
Organisch‐Chemisches Institut Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
Philipp Rohrmann
Organisch‐Chemisches Institut Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
Jonas F. Wunsch
Organisch‐Chemisches Institut Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
Jan Werst
Organisch‐Chemisches Institut Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
Margit Brückner
Organisch‐Chemisches Institut Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
Frank Rominger
Institute of Organic Chemistry
Matthias Rudolph
Organisch‐Chemisches Institut Heidelberg University Im Neuenheimer Feld 270 Heidelberg 69120 Germany
A. Stephen K. Hashmi
Organisch‐Chemisches Institut Heidelberg University Im Neuenheimer Feld 270 Heidelberg 69120 Germany