Synthesis, crystal structures, spectral investigations, conformational analysis and DFT studies of N- heterocyclic carbene precursors

Küçük Resim Yok

Tarih

2020

Dergi Başlığı

Dergi ISSN

Cilt Başlığı

Yayıncı

Elsevier

Erişim Hakkı

info:eu-repo/semantics/closedAccess

Özet

Three new 2-hydroxyethyl substituted N-heterocyclic carbene (NHC) precursors were synthesized in this study. These NHC precursors were prepared from 1-(alkyl/aryl)benzimidazole and alkyl halides. Their structural characterizations were performed by elemental analysis, H-1 NMR, C-13 NMR, FT-IR and UV-Vis spectroscopy and single-crystal X-ray diffraction. The spectral features were also characterized by Density Functional Theory (DFT) at B3LYP/Lanl2dz//6-31G++(d,p) basis set. Two most stable conformers belonging to the compounds were found by potential energy surface (PES) scan, and the theoretical ground-state geometries were investigated. Among these conformers, the geometry of the conformer-I for all compounds matches almost well with the experimental results. H-1 and C-13 NMR chemical shifts were calculated with GLAD approach and compared to the observed ones. Detailed vibrational assignments of the wavenumbers of the conformers were carried out based on the potential energy distribution (PED). Natural bond orbital (NBO) analysis was used to analyze the stability of the molecules arising from hyperconjugative interactions and charge delocalization. The HOMO-LUMO energy gap of the stable conformers was calculated for comparing their chemical reactivity behavior. Molecular electrostatic potential (MEP) diagrams were used to get information about ?the size, shape, charge density distribution and site of chemical reactivity of each stable conformer. The 3D Hirshfeld surfaces and the associated 2D fingerprint plots were also carried out to obtain an insight into the behavior of the interactions in the compounds. (C) 2019 Elsevier B.V. All rights reserved.

Açıklama

Anahtar Kelimeler

N-heterocyclic carbene, Crystal structure, Spectral investigations, Conformational analysis, DFT

Kaynak

Journal of Molecular Structure

WoS Q Değeri

Q3

Scopus Q Değeri

Q2

Cilt

1204

Sayı

Künye