Competition between chalcogen and halogen bonding assessed through isostructural species. Issue 12 (9th November 2022)

• Record Type: Journal Article
• Authors: De Silva, Viraj; Magueres, Pierre Le; Averkiev, Boris B.; Aakeröy, Christer B.
• Is Part Of: Acta crystallographica. Volume 78:Issue 12(2022)
• Page Start: 716
• Page End: 721
• Publication Date: 2022-11-09
• Subjects: halogen bonding -- chalcogen bonding -- Hirshfeld surfaces -- isostructural -- molecular electrostatic potential -- energy framework -- interaction energies -- crystal structure; Crystallography -- Periodicals; Crystals -- Periodicals; 548.3
• DOI: 10.1107/S205322962201052X
• Languages: English
• ISSNs: 2053-2296

Abstract

Abstract : Four isostructural chalcogenadiazole derivatives have been synthesized and characterized using SC‐XRD, MEPs and Hirshfeld surfaces. The structural influence and balance between halogen and chalcogen bonds have been systematically analyzed and rationalized. Abstract : The amino group of 2‐amino‐5‐(4‐halophenyl)‐1, 3, 4‐chalcogenadiazole has been replaced with bromo/iodo substituents to obtain a library of four compositionally related compounds. These are 2‐iodo‐5‐(4‐iodophenyl)‐1, 3, 4‐thiadiazole, C8 H4 I2 N2 S, 2‐bromo‐5‐(4‐bromophenyl)‐1, 3, 4‐selenadiazole, C8 H4 Br2 N2 Se, 2‐bromo‐5‐(4‐iodophenyl)‐1, 3, 4‐selenadiazole, C8 H4 BrIN2 Se, and 2‐bromo‐5‐(4‐iodophenyl)‐1, 3, 4‐thiadiazole, C8 H4 BrIN2 S. All were isostructural and contained bifurcated Ch…N (Ch is chalcogen) and X … X ( X is halogen) interactions forming a zigzag packing motif. The noncovalent Ch…N interaction between the chalcogen‐bond donor and the best‐acceptor N atom appeared preferentially instead of a possible halogen bond to the same N atom. Hirshfeld surface analysis and energy framework calculations showed that, collectively, a bifurcated chalcogen bond was stronger than halogen bonding and this is more structurally influential in this system.