A Theoretically-Guided Optimization of a New Family of Modular P

Identificador:  PC:1258

Handle: https://hdl.handle.net/20.500.11797/PC1258

Autors:  Miquel A. Pericàs; Montserrat Diéguez; Javier Mazuela; Mercè Coll; Erik A. Karlsson; Xisco Caldentey; Jèssica Margalef; Oscar Pàmies

Resum:
A library of modular iridium complexes derived from thioether-phosphite/phosphinite ligands has been evaluated in the asymmetric iridium-catalyzed hydrogenation of minimally functionalized olefins. The modular ligand design has been shown to be crucial in finding highly selective catalysts for each substrate. A DFT study of the transition state responsible for the enantiocontrol in the Ir-catalyzed hydrogenation is also described and used for further optimization of the crucial stereodefining moieties. Excellent enantioselectivities (enantiomeric excess (ee) values up to 99%) have been obtained for a range of substrates, including E- and Ztrisubstituted and disubstituted olefins, a,b-unsaturated enones, tri- and disubstituted alkenylboronic esters, and olefins with trifluoromethyl substituents.