CAAC–IPr*: easily accessible, highly sterically-hindered cyclic (alkyl)(amino)carbenes. Issue 97 (16th November 2022)

• Record Type: Journal Article
• Authors: Chu, Wenchao; Zhou, Tongliang; Bisz, Elwira; Dziuk, Błażej; Lalancette, Roger; Szostak, Roman; Szostak, Michal
• Is Part Of: Chemical communications. Volume 58:Issue 97(2022)
• Page Start: 13467
• Page End: 13470
• Publication Date: 2022-11-16
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1039/d2cc05668b
• Languages: English
• ISSNs: 1359-7345

Abstract

Abstract : We report a merger of CAAC ligands with highly-hindered IPr*. The ligands are strongly electron-rich, bulky and flexible. The availability of various IPr* and CAAC templates offers a significant potential to expand the existing arsenal of NHCs. Abstract : IPr* (IPr* = 1, 3-bis(2, 6-bis(diphenylmethyl)-4-methylphenyl)imidazol-2-ylidene) has emerged as a powerful highly hindered and sterically-flexible ligand platform for transition-metal catalysis. CAACs (CAAC = cyclic (al-kyl)(amino)carbenes) have gained major attention as strongly electron-rich carbon analogues of NHCs (NHC = N-heterocyclic carbene) with broad applications in both industry and academia. Herein, we report a merger of CAAC ligands with highly-hindered IPr*. The efficient synthesis, electronic characterization and application in model Cu-catalyzed hydroboration of alkynes is described. The ligands are strongly electron-rich, bulky and flexible around the N-Ar wingtip. The availability of various IPr* and CAAC templates offers a significant potential to expand the existing arsenal of NHC ligands to electron-rich bulky architectures with critical applications in metal stabilization and catalysis.