Open framework metal monocarboxylates: nickel cyclopropionates containing 16- and 18-membered rings

摘要

We have obtained two layered nickel cyclopropanecarboxylates by using hydrothermal synthesis: Ni_9(OH)_2(H_2O)_6(C_4H_5O_2)_8·2H_1O (1) and Ni_5(OH)_2(C_4H_5O_2)_8 (2). The structures for both materials were solved using single-crystal XRD ((1) Pbcn, a = 14.810(3) A, b = 24.246(5), c = 24.607(5) A, V = 8836(3) A~3, R_1 = 0.0575; (2) Pbcam a = 19.406(4) A, b = 18.466(4) A, c = 21.579(4) A, V = 7733(3) A~3, R_1 = 0.0593). Both structures consist of layers based on 2D Ni-O-Ni networks of NiO_6 octahedra decorated by cyclopropanecarboxylate. The layers in (1) are based on a network of corner- and edge-sharing NiO_6 octahedra forming sheets of 18-member rings, and those in (2) are based on corner-, edge- and face-sharing NiO_6 octahedra forming 16-membered rings. The synthesis of these materials further illustrates that open-frameworks hybrid materials with extended metal-oxygen-metal connectivity may be synthesized with monofunctional carboxylates.