Rotaxanes incorporating two different coordinating units in their thread:: Synthesis and electrochemically and photochemically induced molecular motions
Rotaxanes incorporating two different coordinating units in their thread:: Synthesis and electrochemically and photochemically induced molecular motions
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DOI：
10.1021/ja984051w
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发表时间：
1999-05-12
影响因子：
15
通讯作者：
Ventura, B
中科院分区：
文献类型：
--
作者：
Armaroli, N;Balzani, V;Ventura, B
利用铜(I)的三维模板效应合成了三种不同的多组分分子体系。这些系统包含配位环（含2,9-二苯基-1,10-菲咯啉的30元环）和由两个不同配位位点（2,9-二取代-1,10-菲咯啉和5,5”-二取代-2,2':6',2”-三联吡啶单元）组成的分子链。字符串的每一端都可以通过一个小基团或一个大的终止剂（三（对叔丁基苯基）（4-羟基苯基）甲烷）进行功能分析，从而产生未终止的化合物、半轮烷或真正的轮烷。与二对称铜[2]-链烯的情况一样，通过电化学和光化学方法诱导了大的可逆分子运动。重排过程的驱动力是铜（I）和铜（II）离子两种明显不同的配位环境的高稳定性。在铜(I)态下，两个菲咯啉单元（环中的一个，串中的一个）与金属离子以四面体几何结构（Cu-(4)(I)）相互作用，而在铜（II）态中，属于环的一个菲咯啉和串中的三联吡啶提供了五配位几何结构（Cu-(5)(II)）。与索烷物质相比，分子运动过程的速率（从 Cu-(4)(II) 到 Cu-(5)(II) 和从 Cu-(5)(I) 到 Cu-(4)(I)）分别更快和更慢（分钟时间尺度）。该结果可以根据轮烷和索烷系统之间的结构差异来解释。
Three different multicomponent molecular systems have been synthesized by means of the three-dimensional template effect of copper(I). These systems incorporate both a coordinating ring (2,9-diphenyl-1,10-phenanthroline-containing 30-membered ring) and a molecular string which consists of two different coordination sites (2,9-disubstituted-1,10-phenanthroline and 5,5 "-disubstituted-2,2':6',2 "-terpyridine unit). Each end of the string could be functionnalyzed by a small group or by a bulky stopper (tris(p-tert-butylphenyl)(4-hydroxyphenyl)methane), leading to an unstoppered compound, to a semi-rotaxane, or to a real rotaxane. As in the case of a disymmetrical copper [2]-catenane, large reversible molecular motions have been induced both electrochemically and photochemically. The driving force of the rearrangement processes is the high stability of two markedly different coordination environments for the copper(I) and copper(II) ions. In the copper(I) state, two phenanthroline units (one of the ring, one of the string) interact with the metal ion in a tetrahedral geometry (Cu-(4)(I)), whereas in the copper(II) state, one phenanthroline belonging to the ring and the terpyridine of the string afford a five-coordinate geometry (Cu-(5)(II)). The rates of the molecular motion processes (from Cu-(4)(II) to Cu-(5)(II) and from Cu-(5)(I) to Cu-(4)(I)) are respectively faster and slower (minutes time scale) as compared to those for the catenane species. This result could be interpreted on the basis of structural differences between the rotaxane and catenane systems.