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Steric and Electronic Properties of Indole‐Derived CAAC Ligands
Author(s) -
Termühlen Sebastian,
Dutschke Patrick D.,
Hepp Alexander,
Ekkehardt Hahn F.
Publication year - 2022
Publication title -
european journal of inorganic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.667
H-Index - 136
eISSN - 1099-0682
pISSN - 1434-1948
DOI - 10.1002/ejic.202101065
Subject(s) - chemistry , steric effects , indole test , adduct , homo/lumo , electronic effect , spectroscopy , atomic orbital , crystallography , stereochemistry , computational chemistry , molecule , organic chemistry , physics , quantum mechanics , electron
The electronic properties of two indole‐derived CAAC ligands, featuring N−Et ( II ) or N−H ( IV ) substituents, have been investigated by DFT calculations. The calculations revealed frontier orbitals (HOMO and LUMO) with energies closely related to those of the conventional N‐DIPP substituted CAAC I . The selenium adduct of the N−H substituted CAAC 1 has been prepared and characterized by X‐ray diffraction methods and 77 Se NMR spectroscopy revealing π‐acceptor properties of the CAAC similar to classical CAACs of type I . While the electronic properties of the indole‐derived CAACs II and IV are similar to those of classical CAACs, their % V bur is significantly smaller due to the smaller N‐substituents falling in the range of % V bur for sterically less demanding N‐heterocyclic carbenes.