Аннотация:Abstract A series of chiral, C 2 symmetric tridentate N ‐heterocyclic carbene precursors, containing two N ‐functionalized hydroxyl or alkoxyl groups, were synthesized. They were applied to catalyze the asymmetric conjugate addition of diethylzinc to cyclohex‐2‐enone and cyclopent‐2‐enone. Enantioselectivity of corresponding reactions can be accomplished with up to 76% ee , and 65% ee , respectively. Flip of major enantiomer was observed when different bases or copper sources were utilized.
