Enantioselective addition of silicon nucleophiles to aldimines using a preformed NHC-Copper(I) complex as the catalyst.
A remaining major challenge in the asymmetric addition of silicon nucleophiles to typical prochiral acceptors, the enantioselective 1,2-addition to aldimines, is addressed. Activation of the SiB bond in the silicon pronucleophile by a copper(I) alkoxide with McQuade's chiral six-membered N-heterocyclic carbene as a supporting ligand releases the silicon nucleophile, which adds to various aldimines with high levels of enantioselectivity. The new method provides a catalytic asymmetric access to α-silylated amines.
Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 115, 10623 Berlin (Germany) http://www.organometallics.tu-berlin.de.
Alexander
A
Hensel
Kazuhiko
K
Nagura
Lukas B
LB
Delvos
Martin
M
Oestreich
asymmetric catalysis; carbene ligands; copper; silicon; transmetalation