One-Dimensional Coordination Polymers of Cobalt with 4,4‘-Bipyridine: Syntheses and Structures

Several new one-dimensional coordination polymers were obtained by reactions of different simple cobalt salts
with 4,4‘-bipyridine. Co(SO4)(H2O)3(4,4‘-bipy)·2H2O (1) was obtained by reacting CoSO4 with 4,4‘-bipy in a
water/ethanol solvent system:  hexagonal, P65, a = 11.435(2) Å, c = 20.886(4) Å, Z = 6. CoCl2(DMSO)2(4,4‘-bipy) (2) was crystallized from the reaction of an aqueous solution of CoCl2 with a DMSO solution of 4,4‘-bipy: 
orthorhombic, Pbcn, a = 11.470(2) Å, b = 11.390(2) Å, c = 14.753(1) Å, Z = 4. Reaction of Co(CH3COO)2
with 4,4‘-bipy in water/acetonitrile under hydrothermal conditions yielded Co(CH3COO)2(4,4‘-bipy) (3):  triclinic,
P1̄, a = 7.996(1) Å, b = 9.128(1) Å, c = 10.676(1) Å, α = 109.79(1)°, β = 99.90(1)°, γ = 100.98(1)°, Z = 2.
1 and 2 have structures containing linear Co−bipy−Co chains. In 1, the chains are connected by a network of
hydrogen bonds. The structure of 3 contains linear double Co−bipy−Co chains bridged by CH3COO- groups.
The reaction chemistry observed in different solvent systems and under hydrothermal conditions is discussed.

本研究通过不同简单钴盐与4,4'-联吡啶（4,4'-bipyridine）的反应，合成了多种新型一维配位聚合物。通过硫酸钴（CoSO4）与4,4'-联吡啶在水/乙醇溶剂体系中反应，得到配合物1：Co(SO4)(H2O)3(4,4'-bipy)·2H2O。该晶体属六方晶系，空间群P65，晶胞参数a=11.435(2) Å，c=20.886(4) Å，晶胞内化学式单元数Z=6。通过氯化钴（CoCl2）水溶液与4,4'-联吡啶的二甲基亚砜（Dimethyl sulfoxide，DMSO）溶液反应，得到配合物2：CoCl2(DMSO)2(4,4'-bipy)。该晶体属正交晶系，空间群Pbcn，晶胞参数a=11.470(2) Å，b=11.390(2) Å，c=14.753(1) Å，Z=4。将乙酸钴[Co(CH3COO)2]与4,4'-联吡啶置于水/乙腈混合溶剂中，在水热条件下反应，得到配合物3：Co(CH3COO)2(4,4'-bipy)。该晶体属三斜晶系，空间群P1̄，晶胞参数a=7.996(1) Å，b=9.128(1) Å，c=10.676(1) Å，α=109.79(1)°，β=99.90(1)°，γ=100.98(1)°，Z=2。配合物1与2的晶体结构均包含线性Co-联吡啶-Co链状结构；其中配合物1中的链状结构通过氢键网络相互连接。配合物3的结构则为乙酸根（CH3COO-）桥联的线性双股Co-联吡啶-Co链状结构。本文还探讨了不同溶剂体系及水热条件下的反应化学规律。