Adaptive responses of sterically confined intramolecular chalcogen bonds

Abstract

The existence of intramolecular chalcogen bonds (IChBs) in 2,6-disubstituted arylchalcogen derivatives is determined by the substituents and the sigma hole donor behavior of the chalcogen atom in the molecule.

NMR chiral discrimination of chalcogen containing secondary alcohols

“…This geometry shows the proximity between the chalcogen elements with the oxygen atom from carbonyl group (Se‐O is 3.496 Å and Te‐O is 2.181 Å). These distances could be explained by electrostatic sigma‐hole interactions . Chalcogen bonding (ChB) plays as a conformational lock to stabilize the interaction between nearby heteroatoms (O and N) with low‐valent heavy chalcogen by charge transfer to the antibonding orbital.…”

“…These distances could be explained by electrostatic sigma-hole interactions. 26 Chalcogen bonding (ChB) plays as a conformational lock to stabilize the interaction between nearby heteroatoms (O and N) with low-valent heavy chalcogen by charge transfer to the antibonding orbital. Based on the molecular geometries ( Figure 5), the shortest distance of tellurium element represents a greater sigma-hole interaction.…”

Chalcogen‐Containing Diols: A Novel Chiral Derivatizing Agent for 77Se and 125Te NMR Chiral Recognition of Primary Amines

“…Additionally, a sigma‐hole interaction between the selenium and the oxygen atoms was also observed (Figure ). This effect is, at least in part, a consequence of the intramolecular chalcogen bonding (IChB), a favorable interaction between a heavy chalcogen (Se or Te) with a nearby heteroatom Lewis base‐donor (O or N) . For amine 2 g (Figure ; B), an additional interaction was proposed by the semi‐empirical protocol, indicating a more rigid structure.…”

“…This effect is, at least in part, a consequence of the intramolecular chalcogen bonding (IChB), a favorable interaction between a heavy chalcogen (Se or Te) with a nearby heteroatom Lewis base-donor (O or N). [18] For amine 2 g (Figure 6; B), an additional interaction was proposed by the semi-empirical protocol, indicating a more rigid structure. This interaction could maintain the selenium atom at the same position in both diastereoisomers, suggesting a conformation lock, which does not cause an anisotropic effect in the selenium environment.…”

Contrasting Reactivity of 2‐chloro‐1‐formyl‐3‐hydroxymethylenecyclohexene and its Schiff Bases towards Disodium Diselenide: Isolation of Selenospirocycles versus Azapentalenes

“…The role of intramolecular chalcogen bonding (IChB), an interaction between heavy chalcogen E (E=Se or Te) and an ortho ‐donor atom (O, N, S), in stabilizing organochalcogen derivatives is well documented in literature –. First introduced by Alcock in 1972, ChB is a 3c–4e, donor–acceptor interaction which arises as a result of n 2 (Y)→σ*(E–X) interaction where the lone pair of the donor atom Y (e. g., N, O) interacts with the antibonding σ* orbital of the chalcogen, E (e. g., Se, Te) and a more electronegative atom, X (e. g., Cl, Br).…”