An
asymmetric Mannich-type addition of aldimines and haloacetonitriles
is reported here, yielding halogenated aminonitriles with excellent
stereoselectivity, facilitated by a pincer Ni(II) complex as a catalyst.
Haloacetonitriles are recognized as reactive electrophiles, and the
possibility of their use as a pronucleophile has been almost neglected
for many years. The resulting adduct can be readily converted into
various valuable derivatives, including chiral aziridines, starting
from chlorinated compounds.