作者:Soheila Sameni、Manuel Lejeune、Catherine Jeunesse、Dominique Matt、Richard Welter
DOI:10.1039/b907100h
日期:——
The calix[4]arenes 5-diphenylphosphino-17-R1-11,23-diR2-25,26,27,28-tetrapropoxycalix[4]arene (1, R1 = R2 = Br; 2, R1 = Br, R2 = H; 3, R1 = R2 = p-tolyl; 4, R1 = p-tolyl, R2 = H; 5, R1 = R2 = H; 20, R1 = p-tolyl, R2 = H), all bearing a diphenylphosphino group attached to the calixarene upper rim, have been synthesised starting from 5,11,17,23-tetrabromo-25,26,27,28-tetrapropoxycalix[4]arene. Reaction of 1–5 with [RuCl2(p-cymene)]2 leads quantitatively to monophosphine complexes, [RuCl2(p-cymene)L], in which the endo-oriented ruthenium atom unit sits inside the cone delineated by the four phenoxy rings. The particular orientation of the P–Ru vector appears to result from π–π interactions between the p-cymene ligand and two aromatic cavity walls. Overall, in each case the calixarene end of the ligand behaves as a supramolecular receptor towards the Ru(p-cymene) fragment. Formation of complexes with exo-oriented P–M bonds were observed in the complexes cis-[PtCl2·12] and in [RuCl2(p-cymene)·20]. As shown by a variable temperature study carried out on [RuCl2(p-cymene)·3], in which the ruthenium is embedded in an expanded cone, the p-cymene ring undergoes a fast oscillation about the Ru-arene bond which can be frozen out at low temperatures. Reaction of [RuCl2(p-cymene)·3] with AgBF4 in CH3CN results in an intra-cavity reaction, with one chloride ligand being replaced by acetonitrile.
合成了多种具有二苯基膦基团的钙木[4]芳烃,结构为5-二苯基膦基-17-R1-11,23-二R2-25,26,27,28-四丙氧基钙木[4]芳烃(1, R1 = R2 = Br;2, R1 = Br, R2 = H;3, R1 = R2 = 对甲基苯基;4, R1 = 对甲基苯基, R2 = H;5, R1 = R2 = H;20, R1 = 对甲基苯基, R2 = H),这些化合物是从5,11,17,23-四溴-25,26,27,28-四丙氧基钙木[4]芳烃出发合成的。1-5与[RuCl2(p-cymene)]2的反应定量生成了单膦配合物[RuCl2(p-cymene)L],其中内向的钌原子单元位于由四个酚氧基环界定的锥体内部。P–Ru矢量的特定取向似乎是由p-茨烯配体与两个芳香腔壁之间的π–π相互作用所造成的。总体而言,在每种情况下,配体的钙木芳烃末端表现出对Ru(p-cymene)片段的超分子识别能力。在顺式-[PtCl2·12]和[RuCl2(p-cymene)·20]配合物中观察到了与外向P–M键形成的现象。通过对[RuCl2(p-cymene)·3]进行的变温研究显示,钌被嵌入一个扩展的锥体中,p-茨烯环围绕Ru-芳香环键发生快速振荡,这种振荡可以在低温下被冻结。[RuCl2(p-cymene)·3]与AgBF4在CH3CN中的反应导致腔内反应,其中一个氯配体被乙腈取代。