Estimation of the ability of the π-system of pseudohalides (azide and thiocyanate) to participate in CH···π interactions in cyclic hetero-tetranuclear cobalt(III)/sodium and linear trinuclear mixed valence cobalt(III/II/III) complexes. (1st August 2022)

• Record Type: Journal Article
• Authors: Dastidar, Tamashi Ghosh; Ghosh, Kousik; Drew, Michael G.B.; Gomila, Rosa M.; Frontera, Antonio; Chattopadhyay, Shouvik
• Is Part Of: Polyhedron. Volume 222(2022)
• Publication Date: 2022-08-01
• Subjects: Cobalt(III) -- Cobalt(II) -- Sodium -- Schiff base -- Mixed valence -- Tetra-nuclear -- Tri-nuclear; Chemistry, Inorganic -- Periodicals; Chimie inorganique -- Périodiques; Organometaalverbindingen; Anorganische chemie; 546.05
• DOI: 10.1016/j.poly.2022.115862
• Languages: English
• ISSNs: 0277-5387

Abstract

Graphical abstract: Theoretical calculations have been used to analyze and characterize the conventional π···π stacking and CH···π(arene) interactions and unconventional CH···π(pseudohalide) interactions in a cyclic tetranuclear cobalt(III)/sodium complex and a bent trinuclear Co III (S=0)-Co II (S=3/2)-Co III (S=0) complex. Abstract: A cyclic tetranuclear cobalt(III)/sodium complex, [{(N3 )Co III (L 1 )Na(DMSO)}(μ1, 3 -N3 )2 {(N3 )Co III (L 1 )Na(OH2 )}]2 ⋅0.5CH3 OH (1 ) and a bent trinuclear mixed valence complex [Co II {(μ-L 2 )(μ-OAc)Co III (NCS)}2 ]⋅CH3 CN⋅0.5H2 O (2) have been prepared and their molecular structures have been determined by X-ray crystallography [H2 L 1 = N, N'-bis(3-methoxysalicylidene)-2, 2-dimethyl-1, 3-diaminoproane, H2 L 2 = N, N'-bis(2-hydroxynaphthylmethylidene)propane-1, 3-diamine]. Complex 1 contains two cobalt(III) and two sodium centers, while on the other hand, complex 2 contains a high-spin Co(II) and two terminal low-spin Co(III) centers in a Co III (S = 0)-Co II (S = 3/2)-Co III (S = 0) trimer, as confirmed by DFT calculations Theoretical calculations have been used to analyze the importance of CH···π interactions involving the π-systems of the pseudohalide ligands. Indeed apart from the formation of conventional π···π stacking and CH···π(arene) interactions both complexes exhibit CH···π(pseudohalide) interactions that have been evaluated energetically by using mutated dimers and characterized by means of QTAIM and NCI plot computational methods which can be used to clarify interactions in real space.