Highly Efficient Rhodium-Catalyzed Asymmetric Ring-Opening Reactions of Oxabenzonorbornadiene with Amine Nucleophiles
Rhodium-catalyzed asymmetric ring-opening reactions of oxabenzonorbornadienes with aliphatic primary amines and substituted N-phenylpiperazines were investigated. These reactions are featured with the formation of a new carbon-nitrogen bond via an intermolecular allylic displacement of the bridgehead oxygen with amine nucleophiles, which offered the corresponding products in good to excellent yields (up to 97%) with excellent enantioselectivities (up to 99%ee).
KeywordsRhodium catalysis Asymmetric ring-opening Oxabenzonorbornadienes Chiral bisphosphine ligand
We are grateful to the National Natural Science Foundation of China (No. 20772036 and No. 20802021) and the Natural Science Foundation of Guangdong Province (No. 8251063101000002 and No. 7005804) for financial support.