Ti(IV)/calixarene complexes, formed in situ or previously prepared with standard procedures, can be conveniently used as efficient catalysts in the aldol reaction of Chans silyloxydiene with a range of aldehydes bearing either activating or deactivating groups, including aromatic, heteroaromatic and a,b-unsaturated ones. The structure of both calixarene ligand and aldehyde, as well as the reaction conditions, strongly influence the efficiency of the reaction. NMR experiments in conjunction with the experimental results suggest that the structure of the catalytic species in the Ti(IV)/calixarene system prepared in situ is strongly dependent on the concentration and temperature adopted.
Study on an Aldol Reaction Catalyzed by Ti(IV)/Calix[n]arene Complexes
SORIENTE, Annunziata;DE ROSA, Margherita;GAETA, CARMINE;NERI, Placido
2005-01-01
Abstract
Ti(IV)/calixarene complexes, formed in situ or previously prepared with standard procedures, can be conveniently used as efficient catalysts in the aldol reaction of Chans silyloxydiene with a range of aldehydes bearing either activating or deactivating groups, including aromatic, heteroaromatic and a,b-unsaturated ones. The structure of both calixarene ligand and aldehyde, as well as the reaction conditions, strongly influence the efficiency of the reaction. NMR experiments in conjunction with the experimental results suggest that the structure of the catalytic species in the Ti(IV)/calixarene system prepared in situ is strongly dependent on the concentration and temperature adopted.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
