A comparison between the two most common reduction approaches for obtaining chiral amines, asymmetric hydrogenation (AH) versus asymmetric transfer hydrogenation (ATH), was accomplished by using iridium complexes based on atropoisomeric diphosphines and cyclic diamines as ligands respectively. Seven substrates, different in electronic and steric properties, were screened applying both reduction methods. For AH the best results in terms of enantioselectivity (e.e. up to 64%) were obtained by using [Ir(COD)(TetraMe-BITIOP)]Cl in the presence of DCDMH as additive. ATH was carried out with [IrCp*(CAMPY)Cl]Cl as catalyst, allowing the obtainment of the products with appreciable e.e. (up to 76%).
|Titolo:||Asymmetric Hydrogenation vs Transfer Hydrogenation in the Reduction of Cyclic Imines|
|Data di pubblicazione:||2018|
|Settore Scientifico Disciplinare:||Settore CHIM/03 - Chimica Generale e Inorganica|
Settore CHIM/06 - Chimica Organica
|Parole Chiave:||asymmetric reduction; atropoisomeric diphosphines; cyclic imines; iridium complexes|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1002/slct.201802223|
|Appare nelle tipologie:||1.1 Articolo in rivista|