Alcântara Arthur F P, Fontana Liniquer A, Rigolin Vitor H, Andrade Yuri F S, Ribeiro Marcos A, Barros Wdeson P, Ornelas Catia, Megiatto Jackson D
Institute of Chemistry, University of Campinas (UNICAMP), POBox 6154, 13083-970, Campinas, SP, Brazil.
Instituto Federal do Sertão Pernambucano, Estrada do Tamboril, 56200-000, Ouricuri, PE, Brazil.
Angew Chem Int Ed Engl. 2018 Jul 16;57(29):8979-8983. doi: 10.1002/anie.201803934. Epub 2018 Jun 20.
A Co /porphyrinate-based macrocycle in the presence of a 3,5-diphenylpyridine axial ligand functions as an endotopic ligand to direct the assembly of [2]rotaxanes from diazo and styrene half-threads, by radical-carbene-transfer reactions, in excellent 95 % yield. The method reported herein applies the active-metal-template strategy to include radical-type activation of ligands by the metal-template ion during the organometallic process which ultimately yields the mechanical bond. A careful quantitative analysis of the product distribution afforded from the rotaxane self-assembly reaction shows that the Co /porphyrinate subunit is still active after formation of the mechanical bond and, upon coordination of an additional diazo half-thread derivative, promotes a novel intercomponent C-H insertion reaction to yield a new rotaxane-like species. This unexpected intercomponent C-H insertion illustrates the distinct reactivity brought to the Co /porphyrinate catalyst by the mechanical bond.
在3,5-二苯基吡啶轴向配体存在下，基于钴卟啉的大环作为内源性配体，通过自由基-卡宾转移反应，以95%的优异产率，从重氮和苯乙烯半链组装[2]轮烷。本文报道的方法应用了活性金属模板策略，包括在有机金属过程中金属模板离子对配体的自由基型活化，最终产生机械键。对轮烷自组装反应得到的产物分布进行仔细的定量分析表明，钴卟啉亚基在形成机械键后仍然具有活性，并且在额外的重氮半链衍生物配位后，促进了一种新型的组分间C-H插入反应，生成一种新的类轮烷物种。这种意外的组分间C-H插入说明了机械键给钴卟啉催化剂带来的独特反应性。
