Ugi amine-derived P,N- and P,P-ligands with N-alkyltriethoxysilyl tethers: synthesis and evaluation of mesoporous silica-supported Pd complexes in asymmetric allylic substitution reactions

A facile approach to the synthesis of several types of chiral P,N- and P,P-ligands bearing triethoxysilyl groups starting from N,N-diemthyl-1-ferrocenylethylamine (Ugi amine) has been developed. Allyl palladium complexes of these ligands have been prepared, characterized, and grafted on mesoporous silica. The resulting silica-supported complexes have been shown to catalyze asymmetric allylic alkylation and aminations reactions with moderate enantioselectivities.