A new class of chiral C1-symmetrical diamino-oligothiophene ligands easy-grafted on a soluble polymeric support (MeOPEG5000) is described. The diamines were found to be effective promoting agents for the [Pd(0)]-catalysed asymmetric allylic alkylation (AAA) of dimethyl malonate in high yields and excellent enantioselectivity (ee up to 99%). The supported chiral ligand was readily recovered by precipitation and filtration was recycled up to three times without an appreciable loss in activity. The recycle of the organometallic catalytic system was also investigated. © 2006 Wiley-VCH Verlag GmbH & Co. KGaA.
M. Bandini, M. Benaglia, T. Quinto, S. Tommasi, A. Umani-Ronchi (2006). New Recoverable Poly(ethylen glycol)-supported C1-DAT Ligands for Pd-Promoted AAA Reactions. ADVANCED SYNTHESIS & CATALYSIS, 348(12-13), 1521-1527.
New Recoverable Poly(ethylen glycol)-supported C1-DAT Ligands for Pd-Promoted AAA Reactions
BANDINI, MARCO;TOMMASI, SIMONA;UMANI RONCHI, ACHILLE
2006
Abstract
A new class of chiral C1-symmetrical diamino-oligothiophene ligands easy-grafted on a soluble polymeric support (MeOPEG5000) is described. The diamines were found to be effective promoting agents for the [Pd(0)]-catalysed asymmetric allylic alkylation (AAA) of dimethyl malonate in high yields and excellent enantioselectivity (ee up to 99%). The supported chiral ligand was readily recovered by precipitation and filtration was recycled up to three times without an appreciable loss in activity. The recycle of the organometallic catalytic system was also investigated. © 2006 Wiley-VCH Verlag GmbH & Co. KGaA.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
