| Title: |
Thermotropic Liquid-Crystalline and Light-Emitting Properties of Bis(4-aalkoxyphenyl) Viologen Bis(triflimide) Salts |
| Authors: |
Pradip K. Bhowmik; Muhammed Kareem M. Al-Karawi; Shane T. Killarney; Erenz J. Dizon; Anthony Chang; Jongin Kim; Si L. Chen; Ronald Carlo G. Principe; Andy Ho; Haesook Han; Hari D. Mandal; Raymond G. Cortez; Bryan Gutierrez; Klarissa Mendez; Lewis Sharpnack; Deña M. Agra-Kooijman; Michael R. Fisch; Satyendra Kumar |
| Source: |
Molecules, Vol 25, Iss 2435, p 2435 (2020) |
| Publisher Information: |
MDPI AG |
| Publication Year: |
2020 |
| Collection: |
Directory of Open Access Journals: DOAJ Articles |
| Subject Terms: |
extended viologens; Zincke salt; metathesis reaction; ionic liquid crystals; thermotropic; smectic phase A; Organic chemistry; QD241-441 |
| Description: |
A series of bis(4-alkoxyphenyl) viologen bis(triflimide) salts with alkoxy chains of different lengths were synthesized by the metathesis reaction of respective bis(4-alkoxyphenyl) viologen dichloride salts, which were in turn prepared from the reaction of Zincke salt with the corresponding 4-n-alkoxyanilines, with lithium triflimide in methanol. Their chemical structures were characterized by 1 H and 13 C nuclear magnetic resonance spectra and elemental analysis. Their thermotropic liquid-crystalline (LC) properties were examined by differential scanning calorimetry, polarizing optical microscopy, and variable temperature X-ray diffraction. Salts with short length alkoxy chains had crystal-to-liquid transitions. Salts of intermediate length alkoxy chains showed both crystal-to-smectic A (SmA) transitions, T m s, and SmA-to-isotropic transitions, T i s. Those with longer length of alkoxy chains had relatively low T m s at which they formed the SmA phases that persisted up to the decomposition at high temperatures. As expected, all of them had excellent thermal stabilities in the temperature range of 330–370 °C. Their light-emitting properties in methanol were also included. |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| Relation: |
https://www.mdpi.com/1420-3049/25/10/2435; https://doaj.org/toc/1420-3049; https://doaj.org/article/b88ffea6159541db9f511df2cb8053c0 |
| DOI: |
10.3390/molecules25102435 |
| Availability: |
https://doi.org/10.3390/molecules25102435; https://doaj.org/article/b88ffea6159541db9f511df2cb8053c0 |
| Accession Number: |
edsbas.5D1C233C |
| Database: |
BASE |