Synthetic and structural investigations of bis(N-alkyl-benzoselenadiazolium) cations

Abstract

A variety of supramolecular structures is formed by selenadiazolium cations linked by hydrocarbon bridges.

Bis-selenonium Cations as Bidentate Chalcogen Bond Donors in Catalysis

“…In recent years, using soft chalcogens (group 16 elements such as sulfur and selenium) − as chalcogen bond donors to interact with electron donors (via charge transfer, dispersion, and electrostatic interaction) in intramolecular interaction, − crystal engineering, − supramolecular chemistry, − and conformational control of catalysts are well-documented. An emerging research area involves the use of chalcogens as Lewis acid catalysts.…”

Competing Effects of Chlorination on the Strength of Te⋅⋅⋅O Chalcogen Bonds Select the Structure of Mixed Supramolecular Macrocyclic Aggregates of Iso‐Tellurazole N‐Oxides

“…Chalcogen bonding (ChB), [1–7] i. e. the attractive supramolecular interaction of electrophilic sites on atoms of heavy group 16‐elements (S, Se, Te) with electron‐rich centers, has unveiled an array of fascinating chemistry in fields as diverse as Lewis‐acid catalysis, [8–15] optical probes, [14,16,17] functional materials, [5,18–24] crystal engineering, [25–30] ion recognition and transport, [22,31–36] and protein folding [37] …”

“…DFTÀ D3 calculations indicate that while the halogenated molecule is stronger as a ChB donor it also is a weaker ChB acceptor; the overall effect is that the ChBs in the chlorinated homotetramer are not significantly stronger. However, partial halogenation or scrambling selectively yield the 2 : 2 heterotetramer with alternating λ 4 Te and λ 2 Te centers, which calculations identified as the thermodynamically preferred arrangement.Chalcogen bonding (ChB), [1][2][3][4][5][6][7] i. e. the attractive supramolecular interaction of electrophilic sites on atoms of heavy group 16elements (S, Se, Te) with electron-rich centers, has unveiled an array of fascinating chemistry in fields as diverse as Lewis-acid catalysis, [8][9][10][11][12][13][14][15] optical probes, [14,16,17] functional materials, [5,[18][19][20][21][22][23][24] crystal engineering, [25][26][27][28][29][30] ion recognition and transport, [22,[31][32][33][34][35][36] and protein folding. [37] Amongst the many molecules capable of forming ChBs, isotellurazole N-oxides (1, Scheme 1) stand apart because of their ability to spontaneously assemble cyclic tetramers (1 4 ) and hexamers (1 6 ) that exist in equilibrium in solution.…”

“…Chalcogen bonding (ChB), [1][2][3][4][5][6][7] i. e. the attractive supramolecular interaction of electrophilic sites on atoms of heavy group 16elements (S, Se, Te) with electron-rich centers, has unveiled an array of fascinating chemistry in fields as diverse as Lewis-acid catalysis, [8][9][10][11][12][13][14][15] optical probes, [14,16,17] functional materials, [5,[18][19][20][21][22][23][24] crystal engineering, [25][26][27][28][29][30] ion recognition and transport, [22,[31][32][33][34][35][36] and protein folding. [37] Amongst the many molecules capable of forming ChBs, isotellurazole N-oxides (1, Scheme 1) stand apart because of their ability to spontaneously assemble cyclic tetramers (1 4 ) and hexamers (1 6 ) that exist in equilibrium in solution.…”

Structural study of bioisosteric derivatives of 5-(1H-indol-3-yl)-benzotriazole and their ability to form chalcogen bonds

“…Chalcogen bonds are observed in all of these hits. In particular, chalcogen-interactions are observed in four structures [CSD refcodes: QIBQUQ (Lee et al, 2018), VOPMEV (Lee et al, 2019), VOPNAS (Lee et al, 2019), and YIWLOG (Tan et al, 2008)], listed in Table 2. The search for a benzothiadiazole fragment resulted in 34 hits.…”