聚苯醚的结构效应:1,4-二苯氧基苯和1,4-双(4-甲氧基苯氧基)苯的晶体结构

用单晶X射线衍射分析方法测得1,4-二苯氧基苯(Ⅰ)和1,4-双(4-甲氧基苯氧基)苯(Ⅱ)的晶体结构。它们的晶胞参数分别为:(Ⅰ)α=5.876(2),b=7.832(2),c=1.5455(6)nm, β=95.33(3)°;空间群为P2_1/c,Z=2。(Ⅱ)α=6.017(1),b=7.577(1),c=3.6404(5)nm;空间群为Pcab,Z=4.(Ⅰ),(Ⅱ)的分子构象、键长和键角数据表明氧桥两边的苯环的共轭极化效应不能贯通,而苯氧基只是分子中的一个独立片断。从而也阐明了此类聚苯醚体系的电子吸收光谱的同系直线斜率小的原因。

THE STRUCTURAL EFFECT OF POLYPHENOXY BENZNE COMPOUNDS——THE CRYSTAL STRUCTRE OF 1,4-BIPHENOXYBENZENE AND 1,4-BIS (4-METHOXYPHENOXY) BENZENE

The Crystal structure of 1,4-Biphenoxybenzene (Ⅰ) and 1,4-Bis (4-Methoxyphenoxy) benzene (Ⅱ) have been determined by X-ray diffraction method. For compound (Ⅰ) , the space group is P2_1/c; Its cell parameters are:a=5.876(2), b=7.832(2),c=6.5455(6)nm; β=95.33(3)~0; z=2.For compound (Ⅱ), the space group is Pcab; Its cell parameters are:a=6.017(1),b=7.577(1), c=3.6404 (5)nm;z=4. The bond lengths,bond angles and molecular conformation indicate that:in these polyphenoxy benzene systems the conjugative polarization effect can not pass through the oxygen bridge to cover the whole molecule,Such a strutctural feature explaines its small slope of the homologous line for absorption peaks of polyphenoxy benzene series.