A Series of Mono- and Bis-Alkynyl Co(III) Complexes Supported by a Tetra-imine Macrocyclic Ligand (TIM)
A Series of Mono- and Bis-Alkynyl Co(III) Complexes Supported by a Tetra-imine Macrocyclic Ligand (TIM)
复制标题
DOI：
10.1021/acs.organomet.1c00423
复制
发表时间：
2021-09
期刊：
影响因子：
2.8
通讯作者：
Leobardo Rodriguez Segura;Seul Ah Lee;Brandon L Mash;Ashley J. Schuman;T. Ren
中科院分区：
文献类型：
--
作者：
Leobardo Rodriguez Segura;Seul Ah Lee;Brandon L Mash;Ashley J. Schuman;T. Ren
本文报道了一系列单和双炔基CoIII(TIM)络合物的合成和表征，其中TIM是2,3,9,10-四甲基-1,4,8,11-四氮杂环十四-1,3,8,10-四烯。在 Et3N 存在下，将 HC2Ar 添加到反式-[Co(TIM)Cl2]PF6 中，制备反式-[Co(TIM)(C2Ar)Cl]+ 型配合物（Ar = 苯基（Ph,1a）、萘（Np,1b）和 -C6F5(1c)）。在 MeCN 中用 AgOTf 处理单炔基络合物产生反式-[Co(TIM)(C2Ar)(NCMe)](OTf)2 络合物（Ar = Ph (2a)、Np (2b) 和 -C6F5(2c)）。配合物 2a 和 2 在 Et3N 存在下与相应的 HC2Ar 配体反应，得到对称双炔基配合物反式-[Co(TIM)(C2Ar)2]+(Ar = Ph (3a) 和 Np (3b))。反式-[Co(TIM)(C2C6F5)2]+(3c) 直接从反式-[Co(TIM)Cl2]PF6 与HC2C6F5。此外，在弱碱存在下向 2 添加 HC2Ph，产生不对称双炔基复合物反式-[Co(TIM)(C2C6F5)(C2Ph)]OTf (4)。通过单晶X射线衍射建立了配合物1a/b、2a/b、[3a]PF6、3b和4的分子结构。 1-4 的吸收光谱显示 380 至 470 nm 之间的 d 带。配合物 1b-3b 表现出基于 Np 的荧光。电化学研究表明，所有配合物均表现出 CoIII 中心的不可逆还原特征，以及位于 TIM 大环上的最多两个不可逆还原。
Reported herein is the synthesis and characterization of a series of mono- and bis-alkynyl CoIII(TIM) complexes, where TIM is 2,3,9,10-tetramethyl-1,4,8,11-tetraazacyclotetradeca-1,3,8,10-tetraene. Thetrans-[Co(TIM)(C2Ar)Cl]+type complexes (Ar = phenyl (Ph,1a), naphthalene (Np,1b), and -C6F5(1c)) were prepared by the addition of HC2Ar totrans-[Co(TIM)Cl2]PF6in the presence of Et3N. Treatment of the mono-alkynyl complexes with AgOTf in MeCN resulted in thetrans-[Co(TIM)(C2Ar)(NCMe)](OTf)2complexes (Ar = Ph (2a), Np (2b), and -C6F5(2c)). Complexes2aand2breact with the respective HC2Ar ligand in the presence of Et3N to afford the symmetrical bis-alkynyl complexestrans-[Co(TIM)(C2Ar)2]+(Ar = Ph (3a) and Np (3b)).trans-[Co(TIM)(C2C6F5)2]+(3c) was obtained directly from the prolonged reaction oftrans-[Co(TIM)Cl2]PF6with HC2C6F5. Furthermore, the addition of HC2Ph to2cin the presence of a weak base yielded the unsymmetrical bis-alkynyl complextrans-[Co(TIM)(C2C6F5)(C2Ph)]OTf (4). Molecular structures of complexes1a/b,2a/b, [3a]PF6,3b, and4were established through single crystal X-ray diffraction. The absorption spectra for1–4displayd–dbands between 380 and 470 nm. Complexes1b–3bexhibited Np-based fluorescence. Electrochemical studies revealed that all complexes display an irreversible reduction characteristic of the CoIIIcenter, as well as up to two irreversible reduction(s) localized on the TIM macrocycle.