Polytopic bis(oxazoline)-based ligands for the development of recoverable catalytic systems applied to the cyclopropanation reaction

New ditopic and tetratopic chiral ligands, based on the bis(oxazoline) moiety, have been synthesized and their copper complexes tested as catalysts in the benchmark asymmetric cyclopropanation reaction of styrene with ethyl diazoacetate. The polytopic nature of these ligands enables a release-captur...

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Bibliographic Details
Authors: García, José I., García, Jaime, Herrerías, Clara I., Mayoral, José A., Miñana, Ana C., Sáenz, Carlos
Format: article
Status:Versión aceptada para publicación
Publication Date:2014
Country:España
Institution:Consejo Superior de Investigaciones Científicas (CSIC)
Repository:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/111658
Online Access:http://hdl.handle.net/10261/111658
Access Level:Open access
Keyword:Coordination polymers
Enantioselectivity
Self-supported catalysts
Polytopic ligands
Copper
Polymeri­zation
Description
Summary:New ditopic and tetratopic chiral ligands, based on the bis(oxazoline) moiety, have been synthesized and their copper complexes tested as catalysts in the benchmark asymmetric cyclopropanation reaction of styrene with ethyl diazoacetate. The polytopic nature of these ligands enables a release-capture strategy to efficiently recycle the enantioselective catalyst by precipitation of a coordination polymer at the end of the reaction. This strategy enables the self-supported catalyst to be reused up to 20 times leading to good yields and enantioselectivities.