不同的协调性聚合物与相同的混合干:化学稳定性和结构转换的评估
Chia-Yi Lee1, Yu-Hui Ye1, Song-Wei Wang1
1Department of Chemistry, Chung Yuan Christian University, Chung Li, Taoyuan City 320, Taiwan.
Molecules (Basel, Switzerland)
|April 27, 2024
概括
四个新的协调聚合物被合成使用混合联结体. 它们的结构根据反应条件而异,影响化学稳定性和溶剂相互作用,其中一些呈现可逆转变.
科学领域:
- 协调化学 协调化学
- 材料科学 材料科学 材料科学
- 晶体学 晶体学是指结晶学.
背景情况:
- 金属有机框架 (MOF) 和协调聚合物 (CP) 是使用金属离子和有机链接剂进行合成的.
- 合成聚合物的特性高度依赖于它们的结构,这种结构可以通过不同的合成参数来调整.
研究的目的:
- 使用混合接体合成和表征基于的新型协调聚合物.
- 调查金属与配合物比率,溶剂系统和反应温度对产生的协调聚合物的结构多样性的影响.
- 探索合成复合物的化学稳定性和溶剂诱导的结构转变.
主要方法:
- 单晶X射线晶体学用于四种合成的协调聚合物的结构特征.
- 合成的复合物被浸泡在各种溶剂中,以评估其化学稳定性.
- 进行了溶剂去除和吸附实验,以研究结构转变.
主要成果:
- 四种协调聚合物,{[Co(L) ((SDA) ((H2O) 2}·H2O·CH3OH}n (1),{[Co(L) 0.5 ((SDA) ]·2H2O·0.5L}n (2),{[Co(L) 1.5 ((SDA) ((H2O) ]·H2O}n (3) 和{[Co2(L) 1.5 ((SDA) 2 ((H2O) 2) ·4H2O}n (4),已经成功合成并进行了结构性特征.
- 综合体1-4展示了具有独特拓的二维分层结构 (sql,2,6L1, (4,4) Ia和6L12).
- 发现结构多样性取决于金属与配体的比率,溶剂系统和反应温度. 复合体1和2在溶剂交换时表现出可逆的结构转变,而3和4表现出不可逆的行为.
结论:
- 合成协调聚合物与混合配体 (N,N'-bis(3-pyridylmethyl) oxalamide和4,4'-sulfonyldibenzoic acid) 的合成产生了多样化的二维结构.
- 反应参数显著影响得到的协调聚合物拓和结构完整性.
- 观察到的可逆和不可逆的结构转变凸显了这些材料在应对溶剂相互作用时的动态性质.
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