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  • Structure–property relationships in dicyanopyrazinoquinoxalines and their hydrogen-bonding-capable dihydropyrazinoquinoxalinedione derivatives
Title: Structure–property relationships in dicyanopyrazinoquinoxalines and their hydrogen-bonding-capable dihydropyrazinoquinoxalinedione derivatives
Presented here is the design, synthesis, and study of a variety of novel hydrogen-bonding-capable π-conjugatedN-heteroacenes, 1,4-dihydropyrazino[2,3-b]quinoxaline-2,3-diones (DPQDs). The DPQDs were accessed from the corresponding weakly hydrogen-bonding dicyanopyrazinoquinoxaline (DCPQ) suspensions with excess potassium hydroxide, resulting in moderate to good yields. Both families of compounds were analyzed by UV–vis and NMR spectroscopy, where the consequences of hydrogen bonding capability could be assessed through the structure–property studies. Conversion of the DCPQs into hydrogen-bonding capable DPQDs results in modulation of frontier MO energies, higher molar extinction coefficients, enhanced crystallinity, and on-average higher thermal stability (where in some cases the 5% weight loss temperature is increased by up to 100 °C). Single crystal X-ray diffraction data could be obtained for three DPQDs. One reveals pairwise hydrogen bonding in the solid state as well as a herringbone packing arrangement rendering it a promising candidate for additional studies in the context of organic optoelectronic devices.  more » « less
Award ID(s):
1507561
PAR ID:
10627886
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Beilstein-Institut
Date Published:
Journal Name:
Beilstein Journal of Organic Chemistry
Volume:
20
ISSN:
1860-5397
Page Range / eLocation ID:
1037-1052
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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