Activation of metal-involved halogen bonds and classical halogen bonds in gold(i) catalysis. Issue 14 (15th March 2023)

• Record Type: Journal Article
• Authors: Li, Ying; Sun, Yuanyuan; Zhao, Chang; Zeng, Yanli
• Is Part Of: Dalton transactions. Volume 52:Issue 14(2023)
• Page Start: 4517
• Page End: 4525
• Publication Date: 2023-03-15
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d3dt00158j
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : Both metal-involved halogen bond activation and classical halogen bond activation are investigated in gold(i ) catalysis of the propargylic amide cyclization reaction. Abstract : In gold(i ) catalysis, the activation of Au(i ) chloride catalysts via chloride abstraction and noncovalent interactions has become a research focus in organometallic catalysis. In this work, taking halogen bond donors (C4 H2 INO2, C6 F5 I, C8 H9 O2 I) as activators for a Au(i ) chloride catalyst (Ph3 PAuCl), the mechanism of the cyclization reaction of propargylic amide was investigated. It was found that there are two activation modes as design principles to obtain the catalytically active species Ph3 PAu + : the halogen bond donors activate the Cl atoms of Ph3 PAuCl to form X–I⋯Cl (X = C, N) classical halogen bonds and activate the Au atoms of Ph3 PAuCl to form X–I⋯Au (X = C, N) metal-involved halogen bonds. For the two activation modes, the mechanism of the cyclization reaction of propargylic amide has pathways: the chloride abstraction process of the first step and the 5- exo /6- endo cyclization process of the second step. Both activation modes show good activity for the cyclization reaction with the activation ability of classical halogen bonds being slightly stronger than that of the metal-involved halogen bonds, which is consistent with the strength of the X–I⋯Cl halogen bonds being slightly stronger than that of the X–I⋯Au halogen bonds. Therefore, both metal-involved halogen bonds and classical halogen bonds have important development prospects for the activation of catalysts in gold(i ) catalysis.