Li Ping, Yang Jiayi, Zeng Jiayi, Miao Shuqing, Fang Ran, Lu Jian, Lu Ju-You
School of Chemistry and Chemical Engineering, Hainan University, Haikou 570228, China.
Key Laboratory of Chemical Additives for China National Light Industry, College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China.
Org Lett. 2024 Sep 27;26(38):8134-8138. doi: 10.1021/acs.orglett.4c02966. Epub 2024 Sep 18.
Anionic -carboranes, as open-cage analogues of -carboranes with strong hydrophilicity and higher potential in the development of biomedicines, have been notably more challenging because of their strong interaction with transition metals. While the -cage B-H activation reactions of -carboranes have been widely studied, there are few reports on the direct functionalization of B-H bonds located on a closed polyhedral sphere. Here, we report an efficient palladium-catalyzed regioselective B(2/3)-H alkenylation of -carboranes with various alkenes and alkyne coupling partners, enabled by 3-methylpyridine directing groups, to achieve a regiocontrollable functionalization of B(2/3)-H vertices over highly reactive -cage B11-H vertex in -carboranes.
阴离子型碳硼烷作为碳硼烷的开笼类似物，具有很强的亲水性，在生物医学开发方面具有更高的潜力，但由于它们与过渡金属的强烈相互作用，其研究一直更具挑战性。虽然碳硼烷的笼内B-H活化反应已得到广泛研究，但关于位于封闭多面体球面上的B-H键的直接官能化报道却很少。在此，我们报道了一种高效的钯催化的碳硼烷与各种烯烃和炔烃偶联伙伴的区域选择性B(2/3)-H烯基化反应，该反应由3-甲基吡啶导向基团实现，以实现在碳硼烷中对高反应性的笼内B11-H顶点进行区域可控的B(2/3)-H顶点官能化。
