Sun Yufeng, Guo Jun, Shen Xuzhong, Lu Zhan
Department of Chemistry, Zhejiang University, Hangzhou, 310058, China.
College of Chemistry, Zhengzhou University, Zhengzhou, 450001, China.
Nat Commun. 2022 Feb 3;13(1):650. doi: 10.1038/s41467-022-28285-w.
Sequential double hydrofunctionalizationalization of alkynes is a powerful method to construct useful vicinal compounds. Herein, we report a cobalt-catalyzed sequential hydrosilylation/hydrohydrazidation of alkynes to afford 1,2-N,Si compounds via ligand relay catalysis. A phenomenon of ligand relay is found that the tridentate anionic N-ligand (OPAQ) could capture the cobalt ion from bidentate neutral P-ligand (Xantphos) cobalt complex. This protocol uses three abundant chemical feedstocks, alkynes, silanes, and diazo compounds, and also features operationally simple, mild conditions, low catalyst loading (1 mol%), and excellent functional group tolerance. The 1,2-N,Si compounds can be easily further derivatized to afford various substituted silane derivatives via Si-H functionalization, alcohols via Fleming-Tamao oxidation, free amines and amides via N-N bond cleavage and protection. The asymmetric reaction could also be carried out to afford chiral products with up to 86% ee. The ligand relay has been supported by control experiments and absorption spectra.
炔烃的顺序双氢官能化是构建有用的邻位化合物的有力方法。在此，我们报道了一种钴催化的炔烃顺序硅氢化/氢肼化反应，通过配体接力催化得到1,2-N,Si化合物。发现了一种配体接力现象，即三齿阴离子N-配体（OPAQ）可以从双齿中性P-配体（Xantphos）钴配合物中捕获钴离子。该方法使用了三种丰富的化学原料，炔烃、硅烷和重氮化合物，并且具有操作简单、条件温和、催化剂负载量低（1 mol%）以及出色的官能团耐受性等特点。1,2-N,Si化合物可以通过Si-H官能化轻松进一步衍生得到各种取代硅烷衍生物，通过弗莱明-玉尾氧化得到醇，通过N-N键裂解和保护得到游离胺和酰胺。也可以进行不对称反应以得到对映体过量高达86%的手性产物。控制实验和吸收光谱支持了配体接力。
