Saleh Liban M A, Dziedzic Rafal M, Khan Saeed I, Spokoyny Alexander M
Department of Chemistry and Biochemistry, University of California, Los Angeles (UCLA), 607 Charles E. Young Drive East, Los Angeles, CA, 90095, USA.
Chemistry. 2016 Jun 13;22(25):8466-70. doi: 10.1002/chem.201601292. Epub 2016 May 9.
In contrast to the plethora of metal-catalyzed cross-coupling methods available for the installation of functional groups on aromatic hydrocarbons, a comparable variety of methods are currently not available for icosahedral carboranes, which are boron-rich three-dimensional aromatic analogues of aryl groups. Part of this is due to the limited understanding of the elementary steps for cross-coupling involving carboranes. Here, we report our efforts in isolating metal-boryl complexes to further our understanding of one of these elementary steps, oxidative addition. Structurally characterized examples of group 10 M-B bonds featuring icosahedral carboranes are completely unknown. Use of mercurocarboranes as a reagent to deliver M-B bonds saw divergent reactivity for platinum and palladium, with a Pt-B bond being isolated for the former, and a rare Pd-Hg bond being formed for the latter.
与用于在芳烃上安装官能团的大量金属催化交叉偶联方法形成对比的是，目前对于二十面体碳硼烷（芳基的富硼三维芳香类似物）而言，尚无类似多样的方法。部分原因在于对涉及碳硼烷的交叉偶联基本步骤的了解有限。在此，我们报告了我们为分离金属硼基配合物所做的努力，以进一步加深我们对其中一个基本步骤——氧化加成的理解。具有二十面体碳硼烷的第10族M - B键的结构表征实例完全未知。使用碳硼汞烷作为提供M - B键的试剂时，铂和钯表现出不同的反应性，前者分离出了Pt - B键，而后者形成了罕见的Pd - Hg键。
