Reductive Elimination of Ether from T-Shaped, Monomeric Arylpalladium Alkoxides

摘要

Reductive elimination of ethers from organopalladium alkoxides is the C-O bond-forming step of the palladium-catalyzed etherification of aryl halides. At this time, examples of the reductive eliminations of ethers from isolated organopalladium alkoxide complexes are limited. Only reductive eliminations of alkyl aryl ethers from complexes generated in situ, reductive elimination of an oxygen hetero-cycle from a single oxapalladacycle, reductive eliminations from arylpalladium alkoxides containing activating groups on the aryl ring, and reductive eliminations of biaryl ethers in low yield from isolated complexes are documented. Most importantly, the most active catalysts for the palladium-catalyzed etherification of aryl halides contain sterically hindered monophosphines, and no reductive eliminations from arylpalladium alkoxides containing hindered monophosphines have been described.