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Direct estimate of the internal ?-donation to the carbene centre within N-heterocyclic carbenes and related molecules.

ABSTRACT: Fifteen cyclic and acylic carbenes have been calculated with density functional theory at the BP86/def2-TZVPP level. The strength of the internal X?p(?) ?-donation of heteroatoms and carbon which are bonded to the C(II) atom is estimated with the help of NBO calculations and with an energy decomposition analysis. The investigated molecules include N-heterocyclic carbenes (NHCs), the cyclic alkyl(amino)carbene (cAAC), mesoionic carbenes and ylide-stabilized carbenes. The bonding analysis suggests that the carbene centre in cAAC and in diamidocarbene have the weakest X?p(?) ?-donation while mesoionic carbenes possess the strongest ?-donation.

SUBMITTER: Andrada DM

PROVIDER: S-EPMC4734353 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Direct estimate of the internal π-donation to the carbene centre within N-heterocyclic carbenes and related molecules.

Andrada Diego M DM Holzmann Nicole N Hamadi Thomas T Frenking Gernot G

Beilstein journal of organic chemistry 20151224

Fifteen cyclic and acylic carbenes have been calculated with density functional theory at the BP86/def2-TZVPP level. The strength of the internal X→p(π) π-donation of heteroatoms and carbon which are bonded to the C(II) atom is estimated with the help of NBO calculations and with an energy decomposition analysis. The investigated molecules include N-heterocyclic carbenes (NHCs), the cyclic alkyl(amino)carbene (cAAC), mesoionic carbenes and ylide-stabilized carbenes. The bonding analysis suggests ...[more]

PMID: 26877795

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