当前位置:
X-MOL 学术
›
Chem. Sci.
›
论文详情
Our official English website, www.x-mol.net, welcomes your
feedback! (Note: you will need to create a separate account there.)
Stabilizing an exotic dianionic tetrazine bridge in a Ln2 metallocene
Chemical Science ( IF 7.6 ) Pub Date : 2024-09-06 , DOI: 10.1039/d4sc03734k Niki Mavragani 1 , Alexandros A Kitos 1 , Akseli Mansikkamäki 2 , Muralee Murugesu 1
Chemical Science ( IF 7.6 ) Pub Date : 2024-09-06 , DOI: 10.1039/d4sc03734k Niki Mavragani 1 , Alexandros A Kitos 1 , Akseli Mansikkamäki 2 , Muralee Murugesu 1
Affiliation
The unique electronic nature of the 1,2,4,5-tetrazine or s-tetrazine (tz) ring has sparked tremendous scientific interest over the last few years. Tetrazines have found numerous applications, and their ability to coordinate to metal ions has opened the possibility of exploring their chemistry in both molecular systems and extended networks. The rich redox chemistry of s-tetrazines allows them to exchange electrons and switch between their dihydro (H2tz), neutral (tz), and radical (tz˙−) forms. Previous reports in the literature have observed electrochemically that a second electron can potentially be stored in the tetrazinyl ring and form a dianionic species. However, due to its extremely reactive nature, this has not been isolated before. Herein, the combination of strictly anhydrous and inert conditions, strong reducing agents, non-acidic solvents and most importantly blocking the accessibility of the nitrogen atoms by coordinating them to lanthanide ions allowed for the stabilization of a dianionic tetrazine in a lanthanocene complex. Three dinuclear metallocene complexes are reported, [(Cp*2Ln)2(tz˙−)(THF)2](BPh4) (Ln = Y (1-Y); Cp* = pentamethylcyclopentadienyl; THF = tetrahydrofuran) and [(Cp*2Ln)2(tz2−)(THF)2]·2THF (Ln = Gd (2-Gd), or Y (2-Y)), which utilize the unsubstituted tz as the ligand. In 1-Ln, the tz ligand is reduced to the radical anion (tz˙−), while in 2-Ln, the tz ligand is in the −2 charge state. These complexes are the first structurally and physically characterized complexes bearing the dianion radical of an s-tetrazine. Detailed structural analysis, ab initio calculations, and physical characterization support that the tz2− ligand is a closed-shell planar dianion with unique structural features vastly different from those of the tz, tz˙− and H2tz species.
中文翻译:
稳定 Ln2 茂金属中的奇异双阴离子四嗪桥
1,2,4,5-四嗪或s-四嗪 (tz) 环独特的电子性质在过去几年中引起了巨大的科学兴趣。四嗪已经找到了许多应用,它们与金属离子配位的能力为在分子系统和扩展网络中探索它们的化学提供了可能性。 s-四嗪丰富的氧化还原化学性质使它们能够交换电子并在二氢 (H 2 tz)、中性 (tz) 和自由基 (tz˙ − ) 形式之间切换。文献中先前的报道已经通过电化学观察到第二个电子可能储存在四嗪基环中并形成双阴离子物质。然而,由于其极其活跃的性质,以前并未将其分离出来。在此,严格无水和惰性条件、强还原剂、非酸性溶剂以及最重要的是通过将氮原子与镧系离子配位来阻止氮原子的可接近性的组合使得二茂铁配合物中的双阴离子四嗪得以稳定。 报道了三种双核茂金属配合物,[(Cp* 2 Ln) 2 (tz˙ − )(THF) 2 ](BPh 4 ) (Ln = Y ( 1-Y ); Cp* = 五甲基环戊二烯基; THF = 四氢呋喃) 和 [ (Cp* 2 Ln) 2 (tz 2− )(THF) 2 ]·2THF (Ln = Gd ( 2-Gd ) 或 Y ( 2-Y )),其利用未取代的tz作为配体。在1-Ln中,tz 配体被还原为自由基阴离子 (tz˙ − ),而在2-Ln中,tz 配体处于 -2 电荷态。这些配合物是第一个具有s-四嗪二价阴离子基团的结构和物理特征配合物。详细的结构分析、从头计算和物理表征支持tz 2−配体是一种闭壳平面双阴离子,其独特的结构特征与tz、tz˙ -和H 2 tz 物种的结构特征截然不同。
更新日期:2024-09-06
中文翻译:
稳定 Ln2 茂金属中的奇异双阴离子四嗪桥
1,2,4,5-四嗪或s-四嗪 (tz) 环独特的电子性质在过去几年中引起了巨大的科学兴趣。四嗪已经找到了许多应用,它们与金属离子配位的能力为在分子系统和扩展网络中探索它们的化学提供了可能性。 s-四嗪丰富的氧化还原化学性质使它们能够交换电子并在二氢 (H 2 tz)、中性 (tz) 和自由基 (tz˙ − ) 形式之间切换。文献中先前的报道已经通过电化学观察到第二个电子可能储存在四嗪基环中并形成双阴离子物质。然而,由于其极其活跃的性质,以前并未将其分离出来。在此,严格无水和惰性条件、强还原剂、非酸性溶剂以及最重要的是通过将氮原子与镧系离子配位来阻止氮原子的可接近性的组合使得二茂铁配合物中的双阴离子四嗪得以稳定。 报道了三种双核茂金属配合物,[(Cp* 2 Ln) 2 (tz˙ − )(THF) 2 ](BPh 4 ) (Ln = Y ( 1-Y ); Cp* = 五甲基环戊二烯基; THF = 四氢呋喃) 和 [ (Cp* 2 Ln) 2 (tz 2− )(THF) 2 ]·2THF (Ln = Gd ( 2-Gd ) 或 Y ( 2-Y )),其利用未取代的tz作为配体。在1-Ln中,tz 配体被还原为自由基阴离子 (tz˙ − ),而在2-Ln中,tz 配体处于 -2 电荷态。这些配合物是第一个具有s-四嗪二价阴离子基团的结构和物理特征配合物。详细的结构分析、从头计算和物理表征支持tz 2−配体是一种闭壳平面双阴离子,其独特的结构特征与tz、tz˙ -和H 2 tz 物种的结构特征截然不同。