Smith Graham, Lynch Daniel E
Science and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia.
Exilica Limited, The Technocentre, Puma Way, Coventry CV1 2TT, England.
Acta Crystallogr C Struct Chem. 2014 Jun;70(Pt 6):606-12. doi: 10.1107/S2053229614010596. Epub 2014 May 23.
The two-dimensional polymeric structures of the caesium complexes with the phenoxyacetic acid analogues (4-fluorophenoxy)acetic acid, (3-chloro-2-methylphenoxy)acetic acid and the herbicidally active (2,4-dichlorophenoxy)acetic acid (2,4-D), namely poly[[μ5-(4-fluorophenoxy)acetato][μ4-(4-fluorophenoxy)acetato]dicaesium], [Cs2(C8H6FO3)2]n, (I), poly[aqua[μ5-(3-chloro-2-methylphenoxy)acetato]caesium], [Cs(C9H8ClO3)(H2O)]n, (II), and poly[[μ7-(2,4-dichlorophenoxy)acetato][(2,4-dichlorphenoxy)acetic acid]caesium], [Cs(C8H5Cl2O3)(C8H6Cl2O3)]n, (III), are described. In (I), the Cs(+) cations of the two individual irregular coordination polyhedra in the asymmetric unit (one CsO7 and the other CsO8) are linked by bridging carboxylate O-atom donors from the two ligand molecules, both of which are involved in bidentate chelate Ocarboxy,Ophenoxy interactions, while only one has a bidentate carboxylate O,O'-chelate interaction. Polymeric extension is achieved through a number of carboxylate O-atom bridges, with a minimum Cs···Cs separation of 4.3231 (9) Å, giving layers which lie parallel to (001). In hydrated complex (II), the irregular nine-coordination about the Cs(+) cation comprises a single monodentate water molecule, a bidentate Ocarboxy,Ophenoxy chelate interaction and six bridging carboxylate O-atom bonding interactions, giving a Cs···Cs separation of 4.2473 (3) Å. The water molecule forms intralayer hydrogen bonds within the two-dimensional layers, which lie parallel to (100). In complex (III), the irregular centrosymmetric CsO6Cl2 coordination environment comprises two O-atom donors and two ring-substituted Cl-atom donors from two hydrogen bis[(2,4-dichlorophenoxy)acetate] ligand species in a bidentate chelate mode, and four O-atom donors from bridging carboxyl groups. The duplex ligand species lie across crystallographic inversion centres, linked through a short O-H···O hydrogen bond involving the single acid H atom. Structure extension gives layers which lie parallel to (001). The present set of structures of Cs salts of phenoxyacetic acids show previously demonstrated trends among the alkali metal salts of simple benzoic acids with no stereochemically favourable interactive substituent groups for formation of two-dimensional coordination polymers.
描述了铯与苯氧乙酸类似物（4-氟苯氧基）乙酸、（3-氯-2-甲基苯氧基）乙酸以及具有除草活性的（2,4-二氯苯氧基）乙酸（2,4-D）形成的配合物的二维聚合物结构，即聚[[μ5-(4-氟苯氧基)乙酸根][μ4-(4-氟苯氧基)乙酸根]二铯]，[Cs2(C8H6FO3)2]n，（I）；聚[水合[μ5-(3-氯-2-甲基苯氧基)乙酸根]铯]，[Cs(C9H8ClO3)(H2O)]n，（II）；以及聚[[μ7-(2,4-二氯苯氧基)乙酸根][(2,4-二氯苯氧基)乙酸]铯]，[Cs(C8H5Cl2O3)(C8H6Cl2O3)]n，（III）。在（I）中，不对称单元中两个单独的不规则配位多面体的Cs(+)阳离子（一个CsO7和另一个CsO8）通过来自两个配体分子的桥连羧酸根O原子供体相连，这两个配体分子都参与双齿螯合O羧基、O苯氧基相互作用，而只有一个具有双齿羧酸根O,O'-螯合相互作用。聚合物的延伸通过多个羧酸根O原子桥实现，Cs···Cs的最小间距为4.3231 (9) Å，形成平行于(001)的层。在水合配合物（II）中，Cs(+)阳离子周围的不规则九配位包括一个单齿水分子、一个双齿O羧基、O苯氧基螯合相互作用和六个桥连羧酸根O原子键合相互作用，Cs···Cs间距为4.2473 (3) Å。水分子在平行于(100)的二维层内形成层内氢键。在配合物（III）中，不规则的中心对称CsO6Cl2配位环境包括来自两个双齿螯合模式的氢双[(2,4-二氯苯氧基)乙酸根]配体物种的两个O原子供体和两个环取代的Cl原子供体，以及来自桥连羧基的四个O原子供体。双配体物种位于晶体学反演中心上，通过涉及单个酸H原子的短O-H···O氢键相连。结构延伸形成平行于(001)的层。本组苯氧乙酸铯盐的结构显示了在简单苯甲酸的碱金属盐中先前已证明的趋势，这些简单苯甲酸没有形成二维配位聚合物的立体化学上有利的相互作用取代基。
