Enantioselective Copper-Catalyzed Intramolecular Phenolic O[BOND]H Bond Insertion: Synthesis of Chiral 2-Carboxy Dihydrobenzofurans, Dihydrobenzopyrans, and Tetrahydrobenzooxepines


  • We thank the National Natural Science Foundation of China, the National Basic Research Program of China (2011CB808600), the Ministry of Education of China (B06005), and the Program for New Century Excellent Talents in University (NCET-10-0516) for financial support.


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Efficient: A copper-catalyzed enantioselective intramolecular insertion of carbenoids into phenolic O[BOND]H bonds has been developed. This method can be used for the synthesis of the title compounds in high yields and excellent enantioselectivities under mild and neutral conditions (see scheme). NaBArF=sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate.