Crystallographic and computational study of a network composed of [ZnCl4]2− anions and triply protonated 4′‐functionalized terpyridine cations. Issue 12 (22nd November 2017)

• Record Type: Journal Article
• Authors: Granifo, Juan; Suárez, Sebastián; Boubeta, Fernando; Baggio, Ricardo
• Is Part Of: Acta crystallographica. Volume 73:Issue 12(2017)
• Page Start: 1121
• Page End: 1130
• Publication Date: 2017-11-22
• Subjects: terpyridine -- crystal structure -- anion…π interactions -- Hirshfeld surfaces -- enrichment ratio -- AIM analysis -- computational chemistry; Crystallography -- Periodicals; Crystals -- Periodicals; 548.3
• DOI: 10.1107/S2053229617016308
• Languages: English
• ISSNs: 2053-2296

Abstract

Abstract : The structural analysis of the terpyridine‐based compound (ITPH3 )2 [ZnCl4 ]3 ·H2 O [(ITPH3 ) 3+ is the triply protonated cation of 4′‐(isoquinolin‐4‐yl)‐2, 2′:6′, 2′′‐terpyridine] demonstrates the concerted way in which a variety of noncovalent interactions, viz. hydrogen bonding, π–π and anion…π, participate in the crystal packing. An unexpected large enrichment ratio between the cationic C…N contacts can be understood in the light of their correlation with the atomic and ring NBO (natural bond order) charges. Abstract : We report herein the synthesis, crystallographic analysis and a study of the noncovalent interactions observed in the new 4′‐substituted terpyridine‐based derivative bis[4′‐(isoquinolin‐2‐ium‐4‐yl)‐2, 2′:6′, 2′′‐terpyridine‐1, 1′′‐diium] tris[tetrachloridozincate(II)] monohydrate, (C24 H19 N4 )2 [ZnCl4 ]3 ·H2 O or (ITPH3 )2 [ZnCl4 ]3 ·H2 O, where (ITPH3 ) 3+ is the triply protonated cation derived from 4′‐(isoquinolin‐4‐yl)‐2, 2′:6′, 2′′‐terpyridine (ITP) [Granifo et al. (2016). Acta Cryst. C72, 932–938]. The (ITPH3 ) 3+ cation presents a number of interesting similarities and differences compared with its neutral ITP relative, mainly in the role fulfilled in the packing arrangement by the profuse set of D —H… A [ D (donor) = C, N or O; A (acceptor) = O or Cl], π–π and anion…π noncovalent interactions present. We discuss these interactions in two different complementary ways, viz. using a point‐to‐point approach in the light of Bader's theory of Atoms In Molecules (AIM), analyzing the individual significance of each interaction, and in a more `global' analysis, making use of the Hirshfeld surfaces and the associated enrichment ratio (ER) approach, evaluating the surprisingly large co‐operative effect of the superabundant weaker contacts.