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Tuning the π-Accepting Properties of Mesoionic Carbenes: A Combined Computational and Experimental Study.

ABSTRACT: Mesoionic imidazolylidenes are recognized as excellent electron-donating ligands in organometallic and main group chemistry. However, these carbene ligands typically show poor π-accepting properties. A computational analysis of 71 mesoionic imidazolylidenes that bear different aryl or heteroaryl substituents in C2 position was performed. The study has revealed that a diphenyltriazinyl (Dpt) substituent renders the corresponding carbene particularly π-acidic. The computational results could be corroborated experimentally. A mesoionic imidazolylidene with a Dpt substituent was found to be a better σ-donor and a better π-acceptor compared to an Arduengo-type N-heterocyclic carbene. To demonstrate the utility of the new carbene, the ligand was used to stabilize a low-valent paramagnetic tin compound.

SUBMITTER: Dong Z

PROVIDER: S-EPMC8456875 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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Tuning the π-Accepting Properties of Mesoionic Carbenes: A Combined Computational and Experimental Study.

Dong Zhaowen Z Blaskovits J Terence JT Fadaei-Tirani Farzaneh F Scopelliti Rosario R Sienkiewicz Andrzej A Corminboeuf Clémence C Severin Kay K

Chemistry (Weinheim an der Bergstrasse, Germany) 20210702 46

Mesoionic imidazolylidenes are recognized as excellent electron-donating ligands in organometallic and main group chemistry. However, these carbene ligands typically show poor π-accepting properties. A computational analysis of 71 mesoionic imidazolylidenes that bear different aryl or heteroaryl substituents in C2 position was performed. The study has revealed that a diphenyltriazinyl (Dpt) substituent renders the corresponding carbene particularly π-acidic. The computational results could be co ...[more]

PMID: 34105837

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