Nitro derivatives of 2,1,3-benzothiadiazole 1-oxides: synthesis, structural study, and NO release

Halide Complexes of 5,6‐Dicyano‐2,1,3‐Benzoselenadiazole with 1 : 4 Stoichiometry: Cooperativity between Chalcogen and Hydrogen Bonding

“…Similar to Se…N catemeric 3 [100,113,114] and its TCNQ-fused derivatives [87,115] and N-bonded BR 3 complexes, [82] XRD crystal structure of 1 (Figure 3; SI) does not feature [Se…N] 2 supramolecular dimers observed for many 1,2,5selenadiazoles [51,82,86,91,101,102,116,119] (XRD structure of 2 was not solved due to twinning of available crystals). The [E…N] 2 (E = S, Se, Te) ChBs are attractive and their total bond strength is greater than either ChB individually; and neither a pair of CN substituents in 1,2,5-chalcogenadiazole ring (cf.…”

“…Amongst recently recognized anion receptors, chromogenic/fluorogenic 1,2,5‐chalcogenadiazoles (chalcogen=S, Se, and Te) and their fused derivatives should be highlighted. Their ChB ‐bonded complexes with anions (mostly halides), as well as with neutral Lewis bases, are characterized by XRD, UV‐Vis, NMR, and quantum chemical calculations; in some cases, double ChB is observed to be based on simultaneous participation of two σ‐holes at the same chalcogen atom [51,72–92] . The capacity of chalcogenadiazoles for the formation of ChB increases with the atomic number/polarizability [68] of the chalcogen.…”

Recent Developments in the Synthesis of 1,2,5-Thiadiazoles and 2,1,3-Benzothiadiazoles

“…Surprisingly, that ortho-nitroaniline and other ortho-aminonitroheterocycles gave by treatment with S 2 Cl 2 and a base, sulfurization or chlorine substitution products, which means that the reaction is very sensitive to the structure of the starting material. 4 Scheme 21 Synthesis of fused 1,2,5-thiadiazoles and their 1-oxides from vicinal nitroamines The key steps for the 2,1,3-benzothiadiazoles and their 1-oxide formation from ortho-nitroamino derivatives were rationalized by the sulfurization of the amine with disulfur dichloride to give N-thiosulfinylamines 54, followed by cyclization into 1,2,5-thiadiazole 1-oxide 55 via a cycloaddition/retrocycloaddition with extrusion of sulfur monoxide (SO). The final formation of 1,2,5-thiadiazole 56 from its 1oxide 55 was confirmed by the separate conversion the Noxide 55 to 56 using cyclization reaction conditions (Scheme 22).…”

“…3 6-Nitro-2,1,3-benzothiadiazole 1oxide releases nitric oxide indicating good prospects for this class of compounds as NO donor. 4 4-Amino-2,1,3-benzothiadiazole was reported as a new bidentate directing group for the Pd(II)-catalyzed sp 2 /sp 3 C-H activation/functionalization of various aliphatic/alicyclic/aromatic carboxamide systems. 5 Benzo-and hetareno-fused thiadiazole cores are important moderately electron-deficient building blocks for the construction of various photovoltaic devices: organic and polymer light-emitting diodes (LEDs), 6 organic field-effect transmitters (OFETs), 7 organic dye sensitized solar cells, 8 as polymers for non-linear optics, and near-IR emitters (the literature on this topic is so abundant that only a few references are included).…”

Synthesis and Applications of 5‐Membered Chalcogen‐Nitrogen π‐Heterocycles with Three Heteroatoms

“…For 6‐nitro‐2,1,3‐benzothiadiazole 1‐oxide, high in vitro release of nitric oxide (69%) in the presence of L‐cysteine was observed with the Griess assay, thus making this class of compounds promising to the field …”