A1 Journal article (refereed)
X-ray Crystal Structure and Hirshfeld Analysis of Gem-Aminals-Based Morpholine, Pyrrolidine, and Piperidine Moieties (2021)

Al-Majid, A. M., Haukka, M., Soliman, S. M., Alamary, A. S., Alshahrani, S., Ali, M., Islam, M. S., & Barakat, A. (2021). X-ray Crystal Structure and Hirshfeld Analysis of Gem-Aminals-Based Morpholine, Pyrrolidine, and Piperidine Moieties. Symmetry, 13(1), Article 20. https://doi.org/10.3390/sym13010020

JYU authors or editors

Publication details

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

Journal or series: Symmetry

eISSN: 2073-8994

Publication year: 2021

Volume: 13

Issue number: 1

Article number: 20

Publisher: MDPI AG

Publication country: Switzerland

Publication language: English

DOI: https://doi.org/10.3390/sym13010020

Publication open access: Openly available

Publication channel open access: Open Access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/73787


The gem-aminals of 1,2-dimorpholinoethane (1) and 1-morpholino-3-morpholinium bromide propane (2) were synthesized by reaction of two molar ratio of morpholine with the halogenating agents in the presence of basic condition (K2CO3) in acetone at room temperature (RT) overnight. The structures of the centro-symmetric compound 1 and the morpholinium salt derivative 2 were assigned unambiguous by single crystal X-ray diffraction analysis and compared with the 1,2-di(pyrrolidin-1-yl)ethane 3 and 1,2-di(piperidin-1-yl)ethane 4. The 1,2-dimorpholinoethane molecule has a center of symmetry at the midpoint of the C-C bond of the ethyl moiety leading to two equivalent halves. It crystallized in monoclinic crystal system and P21/n space group, while the unit cell parameters are determined to be a = 6.0430(3), b = 8.0805(3), c = 11.1700(4) Å, and β = 97.475(2)° with unit cell volume of 540.80(4) Å3 and Z = 2 at 170(2) K. The less symmetric analogue 2 crystallized in the lower space group P21 with unit cell parameters of a = 6.37450(10), b = 11.1378(2), c = 9.6549(2) Å, and β = 93.358(2)°, while the unit cell volume is 684.30(2)Å3 at 120(2) K. Using Hirshfeld analysis, the molecules of 1 are mainly packed by weak N…H (4.2%), O…H (16.8%), and H…H (79.0%) interactions. In contrast, the molecules of 2 are packed by significantly short O…H (14.4%) and Br…H (11.6%) interactions in addition to the relatively long H…H (73.3%) interactions. DFT calculations predicted the molecular geometry of the studied compounds showing a good agreement with the experimental X-ray structures. Due to symmetry considerations, compounds 1, 3, and 4 are nonpolar with zero dipole moment, while the less symmetric molecule 2 has a dipole moment of 6.914 Debye. Their electronic aspects, such as natural population charges, HOMO, and LUMO energies as well as the corresponding reactivity descriptors, were also calculated and discussed.

Keywords: organic compounds; amines; x-ray crystallography; density functional theory

Free keywords: aminals; DFT; Hirshfeld analysis; morpholine; piperidine; pyrrolidine; X-ray

Contributing organizations

Ministry reporting: Yes

Reporting Year: 2021

JUFO rating: 1

Last updated on 2022-20-09 at 15:04