Kong W.
Wang Q.
Zhu J.
* École Polytechnique Fédérale de Lausanne, Switzerland
Water as a Hydride Source in Palladium-Catalyzed Enantioselective Reductive Heck Reactions.
Angew. Chem. Int. Ed. 2017;
56: 3987-3991
Key words
palladium catalysis - reductive Heck reaction - oxindoles - hydride source
Significance
Water represents the cheapest and most environmentally benign source of hydrogen or hydride; therefore, its use in combination with transition-metal catalysis is very appealing. In the present work, the authors present a palladium-catalyzed enantioselective reductive Heck reaction using water as final hydride donor.
Comment
N-Aryl acrylamides reacted in the presence of a [PdCl2(MeCN)2] catalyst and (S)-t-BuPHOX ligand to generate the corresponding products in good yields and good enantioselectivities using water as hydride source. The use of DABCO as a base and a catalytic amount of B2(OH)4 was found to be crucial for the success of the transformation. The use of deuterium oxide allowed the synthesis of D-labeled oxindoles with >90% D incorporation.
