A1 Journal article (refereed)
Synthesis of Enaminones-Based Benzo[d]imidazole Scaffold : Characterization and Molecular Insight Structure (2020)

Alshahrani, S., Soliman, S. M., Alamary, A. S., Al-Majid, A. M., Haukka, M., Yousuf, S., & Barakat, A. (2020). Synthesis of Enaminones-Based Benzo[d]imidazole Scaffold : Characterization and Molecular Insight Structure. Crystals, 10(10), Article 955. https://doi.org/10.3390/cryst10100955

JYU authors or editors

Publication details

All authors or editors: Alshahrani, Saeed; Soliman, Saied M.; Alamary, Abdullah Saleh; Al-Majid, Abdullah Mohammed; Haukka, Matti; Yousuf, Sammer; Barakat, Assem

Journal or series: Crystals

eISSN: 2073-4352

Publication year: 2020

Publication date: 21/10/2020

Volume: 10

Issue number: 10

Article number: 955

Publisher: MDPI AG

Publication country: Switzerland

Publication language: English

DOI: https://doi.org/10.3390/cryst10100955

Publication open access: Openly available

Publication channel open access: Open Access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/72472

Abstract

(E)-1-(1H-Benzo[d]imidazol-2-yl)-3-(dimethylamino)prop-2-en-1-one 2 was synthesized by one-pot synthesis protocol of 2-acetyl benzo[d]imidazole with dimethylformamide dimethylacetal (DMF-DMA) in xylene at 140 °C for 8 h. Reaction of enaminone derivative 1 with acetylacetone in the presence of AcOH/NH4OAc under reflux afforded the cyclized pyridino-benzo[d]imidazole derivative 3. The latter compound was converted into the corresponding β-enaminone 4 with DMF-DMA. The single crystal X-ray diffraction technique eventually confirmed the assigned chemical structure of the N-alkyl-β-enaminone 2 and pyridino-benzo[d]imidazole derivative 3. N-alkyl-β-enaminone 2 crystallized in the monoclinic space group P21/n with unit cell parameters of a = 9.8953(3) Å, b = 5.7545(2) Å, c = 21.7891(7) Å, and β =100.627(2)°, and with one molecule per asymmetric unit. On the other hand, compound 3 crystallized in the orthorhombic crystal system and space group P212121 with unit cell parameters of a = 6.82950(10) Å, b = 8.00540(10) Å, c = 22.4779(2) Å, and also with one molecule per asymmetric unit. Based on Hirshfeld analysis, the H...H (51.3%), O...H (10.0%), N...H (10.3%), and C...H (27.6%) contacts in 2 and the H...H (46.8%), O...H (9.9%), N...H (13.0%), and C...H (21.6%) in addition to the C…C (6.7%) interactions in 3 are the most important towards crystal stability via molecular packing. The main difference is the presence of π–π interaction among the molecular units of 3 but not in 2. The calculated 1H and 13C NMR chemical shifts showed good agreements with experimental data. Electronic properties and reactivity parameters of both compounds are also calculated and compared.

Keywords: chemical synthesis; organic compounds; crystals; density functional theory

Free keywords:  benzo[d]imidazole; β-enaminone; DMF-DMA; Hirshfeld analysis; DFT

Contributing organizations

Ministry reporting: Yes

Reporting Year: 2020

JUFO rating: 1