N‐Rich Fused Heterocyclic Systems: Synthesis, Structure, Optical and Electrochemical Characterization

Abstract

A new class of N-rich fused heterocyclic compounds containing the triazolo-triazine moiety was synthesized and studied by cyclic voltammetry, UV/Vis spectroscopy, X-ray diffraction, and first principle computations. All the compounds show reversible or quasi-reversible reduction processes, with reduction potentials easily tunable within the class. LUMO ener-gies as low as –3.95 eV have been measured. The UV/Vis spectra show highly structured absorptions, indicative of rigid molecular skeletons. The solid-state packing is dominated by π–π stacking interactions, which are promoted by weak CAr–H···N interactions, whereas face-to-edge contacts (T contacts), typical of many fused hydrocarbons, are largely absent

Bicyclic 5-6 Systems With One Bridgehead (Ring Junction) Nitrogen Atom: Four Extra Heteroatoms 2:2

“…Such low LUMO value augured a potential use of 28 as a n-type active molecules for organic transistors and organic photovoltaics (Table 1, entries 4-7). 6 With the aim to establish quantitative structure activity relationship (QSAR) for antifungal activities of [1,2,4]triazolo [3,4-b][1,3,4]thiadiazines 30-31, log P and polarizabilities were calculated (Table 1, entries 8-9). 7 <Table 1 near here> Time-dependent density functional theory (TD-DFT) has been used to examine the relationship between molecular structure and the one-and two photon absorption properties of conjugated energetic molecules 4-amino-3,7-dinitro- [1,2,4]triazolo [5,1-c] [1,2,4]triazine derivatives.…”

“…For instance, Fusco et al have reported the condensation of such diamines with various cyclic 1,2-aromatic diketones 385 to furnish the corresponding multicyclic ring systems 386 (entry 1). 6 The reaction was carried out in acetic acid under reflux overnight. Symmetric compound 388 has been obtained by using tetraketone 387 (entry 2).…”

Recent Advances in Heterocyclic Nanographenes and Other Polycyclic Heteroaromatic Compounds

“…Scheme 262 , Section 6.2.1 , for an acenaphthylene analogue). 342 LUMO energy levels were calculated to be −3.77 eV and −3.95 eV for 171.6 and 171.7 , respectively, indicating their potential utility as n-type semiconductors. Condensations with pure enantiomers of 2,2′-diamino-1,1′-binaphthalene 171.1 furnished the chiral systems 171.2 – 3 containing twisted 1,4-diazocine rings.…”

Aminoazole-Based Diversity-Oriented Synthesis of Heterocycles

“…Fusco et al ( 2016 ) applied the condensation between α-diamines 254 and α-diketones 255a–e to obtain triazolo[4,3- b ][1,2,4]triazines 256 in 25–95% yield (the lowest yield for a system with two diketone moieties). An analogous result was obtained for 1,2,5-thiadiazole-3,4-diamine 257 (Planells et al, 2014 ; Figure 20 ).…”