1381949-76-3Relevant articles and documents
Polytopic bis(oxazoline)-based ligands for the development of recoverable catalytic systems applied to the cyclopropanation reaction
Garcia, Jose I.,Garcia, Jaime,Herrerias, Clara I.,Mayoral, Jose A.,Minana, Ana C.,Saenz, Carlos
, p. 1531 - 1540 (2014)
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. The use of polytopic chiral ligands complexes enables efficient recovery of reaction catalyst through precipitation by polymerization following cyclopropanation reactions. The catalyst can then be reused in further reaction cycles with excellent results. Copyright
Asymmetric cyclopropanation in ionic liquids promoted by dicopper complexes of ditopic ligands
García, José I.,Herrerías, Clara I.,López-Sánchez, Beatriz,Mayoral, José A.,Mi?ana, Ana C.
, p. 833 - 837 (2014/06/23)
The use of ionic liquid phases to immobilise dicopper complexes of ditopic chiral ligands bearing bis(oxazoline) moieties has been explored in the enantioselective cyclopropanation reaction of styrene with ethyl diazoacetate. The recoverability of these catalytic phases has been studied using different ionic liquids and ligands. The origin of the ionic liquid is determinant both for the catalytic results and the reusability of the system.