Moving towards Nitrogen‐Based Lewis Acids: A Theoretical Study. Issue 24 (25th June 2018)

• Record Type: Journal Article
• Authors: Ullah, Sabnam S.; Kashyap, Chayanika; Guha, Ankur K.
• Is Part Of: ChemistrySelect. Volume 3:Issue 24(2018)
• Page Start: 6715
• Page End: 6718
• Publication Date: 2018-06-25
• Subjects: annelation -- Density functional calculation -- Lewis acidity; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/slct.201801145
• Languages: English
• ISSNs: 2365-6549

Abstract

Abstract: Density functional calculations predict that reduction of heteroatom in cyclic nitrenium ion increases the Lewis acidity. Calculations also predict that annelation is a very effective way of stabilizing cyclic nitrenium ions and increasing the Lewis acidic character at the nitrenium centre. This is supported by the lowering in the energies of LUMO coupled with the high values of electrophilicity index as well as high hydride affinity. Substituents are also likely to influence their Lewis acidity. Electron withdrawing substituents increases their acidity while electron donating substituents decreases the same. Abstract : Density functional calculations reveal that reduction of heteroatom or by annelation increases the thermodynamic stability and Lewis acidity of cyclic nitrinium ions. Substituents attached to the rings also influence the Lewis acidity. The increased stability is confirmed by their higher hydrogenation energy while the increased acidity is confirmed by their higher hydride ion affinity as well as higher electrophilicity index.