Complexes of zinc halides with amide ligands having a high dipole moment

• Published in: Journal of coordination chemistry 2022-06, Vol.75 (3-4), p.362-371
• Main Authors: Savinkina, Elena V., Efimova, Natalia A., Grigoriev, Mikhail S., Davydova, Margarita N., Fomichev, Valery V., Ageeva, Tatyana A.
• Format: Article
• Language: English
• Subjects: Amides; Benzamide; Cellulose diacetate; Chemical analysis; Dimethylformamide; dipole moment; Dipole moments; Halides; Infrared spectroscopy; Ligands; Oxygen atoms; urea; Ureas; Zinc; Zinc bromide
• ISSN: 0095-8972; 1029-0389
• DOI: 10.1080/00958972.2022.2054704

Complexes [Zn(C 6 H 5 CONH 2 ) 2 Br 2 ] and [Zn((NH 2 ) 2 CO) 2 Br 2 ] were synthesized and characterized by elemental analysis, IR spectroscopy, and X-ray diffraction and compared to other complexes of zinc halides with benzamide and urea. In all complexes, the zinc ion has a tetrahedral coordination environment of two halide ligands and two oxygen atoms of two amide ligands. The structure of [Zn(C 6 H 5 CONH 2 ) 2 Br 2 ] (orthorhombic, Pna2 1 , a = 29.207(6), b = 7.5826(14), c = 14.753(3) Å, Z = 8) is not isostructural to the chloride and iodide compounds. The [Zn((NH 2 ) 2 CO) 2 Br 2 ] complex (triclinic, P-1, a = 6.4435(9), b = 7.096(1), c = 11.7079(18) Å, α = 88.119(9)°, β = 77.005(9)°, γ = 66.320(8)°, Z = 2) is isostructural to [Zn((NH 2 ) 2 CO) 2 Cl 2 ], and they both differ from [Zn((NH 2 ) 2 CO) 2 I 2 ]. Dipole moments of complexes of various zinc halides with benzamide, urea, and dimethylformamide were calculated; they vary in the 9-13 D range. Complexes of zinc halides with amides were used to prepare films with the use of cellulose diacetate as a polymer matrix. Dielectric measurements showed the presence of a pronounced electret effect.