Asymmetric Azide–Alkyne Cycloaddition with Ir(I)/Squaramide Cooperative Catalysis: Atroposelective Synthesis of Axially Chiral Aryltriazoles
Xue Zhang, Shunian Li, Wenjing Yu, Yufang Xie, Chen‐Ho Tung, Zhenghu Xu
Abstract
An Ir(I)/squaramide cooperative catalytic strategy for atroposelective synthesis of axially chiral aryltriazoles has been developed for the first time. Diverse structurally novel aryltriazole skeletons that cannot be accessed by traditional click reactions were synthesized in good yields with excellent enantioselectivity. Both enantiomers were easily obtained from a pair of diastereoisomeric natural quinidine- and quinine-derived squaramides. A significant Ir(I)/squaramide coordination activation, but no self-quenching phenomenon was observed in this metal/organo cooperative catalytic system.
Topics & Concepts
SquaramideChemistryAzideCycloadditionCatalysisCombinatorial chemistryEnantiomerQuenching (fluorescence)CinchonaOrganic chemistryEnantioselective synthesisOrganocatalysisPhysicsFluorescenceQuantum mechanicsAxial and Atropisomeric Chirality SynthesisCatalytic C–H Functionalization MethodsSphingolipid Metabolism and Signaling