{"title":"A crystalline trianionic triangular triboron species","authors":"Zhongtao Feng, Rei Kinjo","doi":"10.1016/j.chempr.2024.07.017","DOIUrl":null,"url":null,"abstract":"<p>Coulomb repulsion in multiply charged ions (MCIs) is mitigated by long-range electrostatic interaction with the distant charge separation and delocalized systems. Meanwhile, MCIs featuring the charged centers located at two directly connected atoms (E<sup>+/−</sup>–E<sup>+/−</sup>) bear a strong repulsive force, which leads to electron detachment or molecular fragmentation, namely, Coulomb explosion. Here, we describe the synthesis of a trianionic triangular triboron species (B<sub>3</sub>R<sub>6</sub><sup>3−</sup>) through the reductive dealumination from a Cp∗AlB<sub>3</sub>R<sub>6</sub> anion (Cp∗, 1,2,3,4,5-pentamethylcyclopentadienyl). X-ray crystallographic and spectroscopic analyses with the aid of quantum chemical calculations reveal that despite the triply negatively charged skeleton, the B<sub>3</sub> core is tightly held by electron-precise B–B bonds, overcoming Coulomb repulsion. In contrast to the extant electron-deficient triborate rings, this molecule exhibits reducing ability and nucleophilicity; thus, it undergoes not only electron transfer but also cyclization and salt metathesis reactions, demonstrating its trait as elusive (R<sub>2</sub>B<sup>−</sup>) and ([R<sub>2</sub>B]<sub>2</sub><sup>2−</sup>) surrogates.</p>","PeriodicalId":268,"journal":{"name":"Chem","volume":null,"pages":null},"PeriodicalIF":19.1000,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Chem","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.1016/j.chempr.2024.07.017","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Coulomb repulsion in multiply charged ions (MCIs) is mitigated by long-range electrostatic interaction with the distant charge separation and delocalized systems. Meanwhile, MCIs featuring the charged centers located at two directly connected atoms (E+/−–E+/−) bear a strong repulsive force, which leads to electron detachment or molecular fragmentation, namely, Coulomb explosion. Here, we describe the synthesis of a trianionic triangular triboron species (B3R63−) through the reductive dealumination from a Cp∗AlB3R6 anion (Cp∗, 1,2,3,4,5-pentamethylcyclopentadienyl). X-ray crystallographic and spectroscopic analyses with the aid of quantum chemical calculations reveal that despite the triply negatively charged skeleton, the B3 core is tightly held by electron-precise B–B bonds, overcoming Coulomb repulsion. In contrast to the extant electron-deficient triborate rings, this molecule exhibits reducing ability and nucleophilicity; thus, it undergoes not only electron transfer but also cyclization and salt metathesis reactions, demonstrating its trait as elusive (R2B−) and ([R2B]22−) surrogates.
期刊介绍:
Chem, affiliated with Cell as its sister journal, serves as a platform for groundbreaking research and illustrates how fundamental inquiries in chemistry and its related fields can contribute to addressing future global challenges. It was established in 2016, and is currently edited by Robert Eagling.