163. The structure of molecular compounds. Part VI. The β-type clathrate compounds of quinol
163. The structure of molecular compounds. Part VI. The β-type clathrate compounds of quinol
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163. 分子化合物的结构第六部分。
DOI：
10.1039/jr9480000815
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发表时间：
1948
期刊：
影响因子：
--
通讯作者：
H. M. Powell
中科院分区：
文献类型：
--
作者：
D. Palin;H. M. Powell
理想式3喹啉：M的结晶化合物具有共同的结构组分，由喹啉单位氢键形成两个独立的相互穿透的大分子，它们一起包裹着第二组分的小分子M。记录了M为SO，， MeOH, HC1, HBr， H， S， C， H,， HCO， H， CO,， MeCN的化合物的x射线和其他数据。混合化合物也被制备与两种不同类型的分子在外壳。从单胞尺寸和密度进行的分析和分子量测定一致表明，由于M的许多空腔未被占用，可能与理想公式有相当大的偏离。对于M分子足够小的几种化合物，喹啉结构的尺寸几乎是恒定的，并由两个相互穿透的大分子的平衡决定。较大的封闭分子在单位细胞的尺寸上产生微小的变化，沿着六边形细胞的c方向扩展喹啉框架，并同时以直角收缩它，其效果类似于一块网格的延伸而不改变其组成部分的尺寸。这些变化与封闭分子的尺寸有关。在不改变喹啉单元或其连接氢键的羟基六边形的尺寸的情况下，对喹啉笼结构的形状进行了轻微的改变，使腔体可以容纳不同的分子m。这些结构变化与该系列中弱双折射的变化有关。在第四部分（鲍威尔，本卷，第61页）中，讨论了一类分子被另一类分子包围而形成的笼合物的形成条件和某些性质。第11部分和第5部分详细给出的晶体结构（Palin and Powell， J., 1947, 209；本卷，第571页）表明，两个相互穿透的氢键喹啉单位大分子可能以这种方式将分子M包围在一起，形成如图所示的配合物，并且被包围的分子有一定的运动自由，这些分子虽然被牢牢地保留下来，但不需要与周围环境紧密结合。本通讯包含对该系列化合物的一些其他成员进行结构检查的结果，以确定是否存在恒定的结构类型，并发现改变封闭分子的类型和浓度的影响。其中一些化合物以前已经制备过（参考文献，见第111部分），现在发现，只要满足一定的尺寸要求，并且在制备条件下不与喹啉发生化学反应，各种类型的分子都可以用这种方法包裹起来。通常还需要添加的组分以分子形式存在于含有足够浓度的喹啉的溶液中，以确保其在构建结构过程中被捕获，尽管有时可能采用其他制备方法。
Crystalline compounds of ideal formula 3 quinol: M are shown to have a common structural component consisting of quinol units hydrogen bonded to form two independent interpenetrating giant molecules which together enclose small molecules M of the second component. X-Ray and other data are recorded for the compounds where M is SO,, MeOH, HC1, HBr, H, S, C, H,, HCO, H, CO,, MeCN. Mixed compounds have also been prepared with two different kinds of molecule in the enclosures. Analyses and molecular-weight determinations from unit-cell dimensions and densities are in agreement in showing that there may be considerable departure* from the ideal formula through many of the cavities available for M being unoccupied. For several compounds in which M is a sufficiently small molecule the dimensions of the quinol structure are almost constant and are determined by the equilibrium of the two interpenetrating giant molecules. The larger enclosed molecules produce minor alterations in the unit-cell dimensions, distending the quinol framework along the c direction of the hexagonal cell and contracting it simultaneously at right angles by an effect analogous to the extension of a piece of trellis without alteration in the dimensions of its component parts. These variations have been correlated with the dimensions of the enclosed molecules. Slight alterations in the shape of the quinol cagework, without alteration in the dimensions of the quinol units or their connecting hydrogen-bonded hexagons of OH groups, are made so that the cavities may accommodate the different molecules M. These structural changes have been correlated with the variations in the weak birefringence in the series.IN Part IV (Powell, this vol., p. 6l), the conditions of formation and some properties of clathrate compounds formed by enclosure of one kind of molecule by others are discussed. The crystal structures given in detail in Parts I11 and V (Palin and Powell, J., 1947, 209; this vol., p. 571) show that two interpenetrating giant molecules of hydrogen-bonded quinol units may together enclose molecules M in this way to give complexes formulated as shown, and that there is some freedom of movement of the enclosed molecule which, although firmly retained, need not be closely bound to its surroundings. The present communication contains the results of structural examinations made on some other members of this series of compounds in order to determine whether there is a constant structural type and to find the effects of varying the type and concentration of the enclosed molecule. Some of these compounds have been prepared previously (for references, see Part 111) and it is now found that molecules of varied type may be enclosed in this way provided that they satisfy certain size requirements, and do not react chemically with quinol in the conditions of preparation. It is also normally necessary that the added component should exist in the form of molecules in solution with quinol in sufficient concentration to ensure its being trapped during the building up of the structure, although other methods of preparation may sometimes be possible.