Tricyanoborane‐Functionalized Anionic N‐Heterocyclic Carbenes: Adjustment of Charge and Stereo‐Electronic Properties
Please always quote using this URN: urn:nbn:de:bvb:20-opus-287200
- The 1‐methyl‐3‐(tricyanoborane)imidazolin‐2‐ylidenate anion (2) was obtained in high yield by deprotonation of the B(CN)3‐methylimidazole adduct 1. Regarding charge and stereo‐electronic properties, anion 2 closes the gap between well‐known neutral NHCs and the ditopic dianionic NHC, the 1,3‐bis(tricyanoborane)imidazolin‐2‐ylidenate dianion (IIb). The influence of the number of N‐bonded tricyanoborane moieties on the σ‐donating and π‐accepting properties of NHCs was assessed by quantum chemical calculations and verified by experimental data onThe 1‐methyl‐3‐(tricyanoborane)imidazolin‐2‐ylidenate anion (2) was obtained in high yield by deprotonation of the B(CN)3‐methylimidazole adduct 1. Regarding charge and stereo‐electronic properties, anion 2 closes the gap between well‐known neutral NHCs and the ditopic dianionic NHC, the 1,3‐bis(tricyanoborane)imidazolin‐2‐ylidenate dianion (IIb). The influence of the number of N‐bonded tricyanoborane moieties on the σ‐donating and π‐accepting properties of NHCs was assessed by quantum chemical calculations and verified by experimental data on 2, IIb, and 1,3‐dimethylimidazolin‐2‐ylidene (IMe, IIa). Therefore NHC 2, which acts as a ditopic ligand via the carbene center and the cyano groups, was reacted with alkyl iodides, selenium, and [Ni(CO)\(_{4}\)] yielding alkylated imidazoles 3 and 4, the anionic selenium adduct 5, and the anionic nickel tricarbonyl complex 8, respectively. The results of this study prove that charge, number of coordination sites, buried volume (%V\(_{bur}\)) and σ‐donor and π‐acceptor abilities of NHCs can be effectively fine‐tuned via the number of tricyanoborane substituents.…
Author: | Ludwig Zapf, Sven Peters, Rüdiger Bertermann, Udo Radius, Maik Finze |
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URN: | urn:nbn:de:bvb:20-opus-287200 |
Document Type: | Journal article |
Faculties: | Fakultät für Chemie und Pharmazie / Institut für Anorganische Chemie |
Language: | English |
Parent Title (English): | Chemistry – A European Journal |
Year of Completion: | 2022 |
Volume: | 28 |
Issue: | 39 |
Article Number: | e202200275 |
Source: | Chemistry – A European Journal 2022, 28(39):e202200275. DOI: 10.1002/chem.202200275 |
DOI: | https://doi.org/10.1002/chem.202200275 |
Dewey Decimal Classification: | 5 Naturwissenschaften und Mathematik / 54 Chemie / 540 Chemie und zugeordnete Wissenschaften |
Tag: | N-heterocyclic carbene; anionic carbene; boron; cyanoborate; imidazolate |
Release Date: | 2023/01/18 |
Licence (German): | CC BY-NC-ND: Creative-Commons-Lizenz: Namensnennung, Nicht kommerziell, Keine Bearbeitungen 4.0 International |