A New Method of α-Functionalization for Tertiary Amines by Nucleophilic Substitution of α-Siloxy Amines

Article abstract of DOI:10.1246/bcsj.61.735

α-Siloxy amines, which were easily prepared by "silicon Polonovski reaction" of tertiary amine N-oxides with trialkylsilyl trifluoromethanesulfonate, were treated with various nucleophiles to give the corresponding α-functionalized tertiary amines in moderate to good yields.This new method has to the advantage that it enables the α-substitution of amines not only by alkyl groups but also by alkenyl and aryl groups with sp² carbon as a reaction center, since the introduction of such groups is difficult in electrophilic substitution of dipole-stabilized α-lithio amines.Besides the organometallics such as Grignard and organoaluminum reagents, trimethylsilyl cyanide and silyl enol ether could also be employed as nucleophiles in the presence of an appropriate Lewis acid.