Structure of copper(II) complexes grown from ionic liquids – 1-ethyl-3-methylimidazolium acetate or chloride

• Published in: Acta crystallographica. Section E, Crystallographic communications Crystallographic communications, 2018-07, Vol.74 (7), p.981-986
• Main Authors: Serov, Nikita Yu, Shtyrlin, Valery G., Islamov, Daut R., Kataeva, Olga N., Krivolapov, Dmitry B.
• Format: Article
• Language: English
• Subjects: copper(II) complexes; crystal structure; ionic liquids; paddle-wheel
• ISSN: 2056-9890; 2056-9890
• DOI: 10.1107/S2056989018008538

Crystals of four new copper(II) complexes have been grown from copper(II) acetate/chloride–1-ethyl-3-methylimidazolium acetate/chloride–water systems and characterized by X-ray analysis. The first complex, bis(1-ethyl-3-methylimidazolium) tetra-μ-acetato-bis[chloridocuprate(II)], [Emim] 2 [Cu 2 (C 2 H 3 O 2 ) 4 Cl 2 ] ( 1 ) (Emim is 1-ethyl-3-methylimidazolium, C 6 H 11 N 2 ), contains [Cu 2 (C 2 H 3 O 2 ) 4 Cl 2 ] 2− coordination anions with a paddle-wheel structure and ionic liquid cations. Two of the synthesized complexes are one-dimensional polymers, namely catena -poly[1-ethyl-3-methylimidazolium [[tetra-μ-acetato-dicuprate(II)]-μ-chlorido] monohydrate], {[Emim][Cu 2 (C 2 H 3 O 2 ) 4 Cl]·H 2 O} n ( 2 ), and catena -poly[1-ethyl-3-methylimidazolium [[tetra-μ-acetato-dicuprate(II)]-μ-acetato]], {[Emim][Cu 2 (C 2 H 3 O 2 ) 5 ]} n ( 3 ). In these compounds, the Cu 2 (C 2 H 3 O 2 ) 4 units with a paddle-wheel structure are connected to each other through chloride (in 2 ) or acetate (in 3 ) anions to form parallel chains, between which cations of ionic liquid are situated. The last compound, bis(1-ethyl-3-methylimidazolium) tetra-μ-acetato-bis[aquacopper(II)] tetra-μ-acetato-bis[acetatocuprate(II)] dihydrate, [Emim] 2 [Cu 2 (C 2 H 3 O 2 ) 4 (H 2 O) 2 ][Cu 2 (C 2 H 3 O 2 ) 6 ]·2H 2 O ( 4 ), contains two different binuclear coordination units (neutral and anionic), connected through hydrogen bonds between water molecules and acetate ions.