Synthesis of chiral vicinal diamines for asymmetric catalysts

Abstract

The vicinal-diamine functionality is widely exploited as a source of chirality in many organic chemical processes. Chiral vicinal diamines have been used to develop numerous chiral catalysts including transition metal catalysts and organocatalysts. Many of these organocatalysts combine the chiral primary amine group with another functional group (thiourea, urea, sulfonamide, etc.). Inspired by natural enzymes, urea or guanidine structure from vicinal diamine was set as the catalyst to stabilize and deliver fluoride ion in order to develop catalytic asymmetric fluorination reaction. In the chiral diamine backbone, hydrogen bonding donors and a primary amine reaction center are introduced. N-heterocyclic carbenes (NHCs) have been widely used, but the design of chiral NHCs for enantioselective reactions remains as a challenge. we are working on obtaining C2-symmetric NHCs from trans-1,2-substituted ethylendiamines by the diaza-Cope rearrangement and N-arylation. These structures can be used for organocatalysts or transition metal ligands.