The cycloaddition reaction of ethylene and methane mediated by Ir+ to generate a half-sandwich structure IrHCp+

The cycloaddition reactions of methane and ethylene mediated by Ir+ have been designed and studied by the techniques of mass spectrometry in conjunction with theoretical calculations. Studies have shown that Ir+ can mediate the cycloaddition reaction of CH4 and two C2H4 to generate a half-sandwich structure IrHCp+ (Cp = eta(5) -C5H5) including pentamethylcyclopentadienyl ligand by continuous dehydrogenation reaction with the forming of three C-C bonds and seven C-H bonds. The orbital analysis indicates the mechanism of the cyclization reaction to generation of pentamethylcyclopentadienyl ligand with odd number carbon atom depends on the overlap of pi orbitals in -C2H2 and carbene, which is more difficult than the forming of cyclobutadiene ligand and benzene. This study may help to understand the reaction mechanism in the cycloaddition reactions of organic compounds, which will be useful to guide the rational design of new catalysts with tailored selectivity and increased efficiency. (c) 2022 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.

Automated summary

The cycloaddition reactions of methane and ethylene mediated by Ir+ have been studied using mass spectrometry and theoretical calculations. The results show that Ir+ can facilitate the cycloaddition reaction to generate a half-sandwich structure IrHCp+ including a pentamethylcyclopentadienyl ligand. The study provides insights into the reaction mechanism and may guide the design of new catalysts with improved selectivity and efficiency.