title: Tuning the electronic and ligand properties of remote carbenes: a theoretical study.
abstract: The effect of annulation and carbonylation on the electronic and ligating properties of remote N-heterocyclic carbenes (rNHCs) has been studied quantum-chemically. The thermodynamic stability of these complexes has been assessed on the basis of their hydrogenation and stabilization energies, while HOMO-LUMO gaps are used to measure the kinetic stabilities. Annulated/carbonylated rNHCs are found to be weaker σ donors but better π acceptors compared with the parent rNHCs. The reactivity of these rNHCs has been studied by evaluating their nucleophilicity and electrophilicity indices. The nucleophilicity values are in good agreement with the σ basicities of all of the rNHCs. The (31)P NMR chemical shifts of the corresponding rNHC-phosphinidene adducts have been calculated and found to correlate well with the π acidities of these rNHCs.
authors.affiliation: Department of Chemical Sciences, Tezpur University , Napaam 784028, Assam, India.
authors.forename: Bitupon
authors.initials: B
authors.lastname: Borthakur
authors.forename: Taskia
authors.initials: T
authors.lastname: Rahman
authors.forename: Ashwini K
authors.initials: AK
authors.lastname: Phukan
mesh_terms: D004581:Electronics; D006571:Heterocyclic Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D008962:Models, Theoretical; D011789:Quantum Theory
chemical_list: D006571:Heterocyclic Compounds; D008024:Ligands; C030011:carbene; D008697:Methane