Development of chiral phosphoric acids based on ferrocene-bridged paracyclophane frameworks
نویسندگان
چکیده
This work deals with the development of a new family of planar chiral phosphoric acids, based on a ferrocenophane/paracyclophane scaffold. The synthetic approach has been improved by taking advantage of a chiral phosphorylating agent to access enantiomerically enriched acids via diastereomers separation. These phosphoric acids have been used as catalysts for the enantioselective H-transfer reduction of -substituted quinolines with Hantzsch esters. Optimization of both the catalyst and the Hantzsch reductant allowed ee in the range 82-92% to be attained starting from -arylquinolines.
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