Thenarukandiyil Ranjeesh, Satheesh Vanaparthi, Shimon Linda J W, de Ruiter Graham
Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City, 3200008, Haifa, Israel.
Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, 7610001, Israel.
Chem Asian J. 2021 Apr 19;16(8):999-1006. doi: 10.1002/asia.202100003. Epub 2021 Mar 22.
During the past decade earth-abundant metals have become increasingly important in homogeneous catalysis. One of the reactions in which earth-abundant metals have found important applications is the hydroboration of unsaturated C-C and C-X bonds (X=O or N). Within these set of transformations, the hydroboration of challenging substrates such as nitriles, carbonates and esters still remain difficult and often relies on elaborate ligand designs and highly reactive catalysts (e. g., metal alkyls/hydrides). Here we report an effective methodology for the hydroboration of challenging C≡N and C=O bonds that is simple and applicable to a wide set of substrates. The methodology is based on using a manganese(II) triflate salt that, in combination with commercially available potassium tert-butoxide and pinacolborane, catalyzes the hydroboration of nitriles, carbonates, and esters at room temperature and with near quantitative yields in less than three hours. Additional studies demonstrated that other earth-abundant metal triflate salts can facilitate this reaction as well, which is further discussed in this report.
在过去十年中，储量丰富的金属在均相催化中变得越来越重要。储量丰富的金属已获得重要应用的反应之一是不饱和碳 - 碳和碳 - 卤键（X = O或N）的硼氢化反应。在这些转化反应中，腈、碳酸酯和酯等具有挑战性的底物的硼氢化反应仍然很困难，并且通常依赖于精心设计的配体和高活性催化剂（例如金属烷基化物/氢化物）。在此，我们报告了一种用于具有挑战性的碳 - 氮三键和碳 - 氧双键硼氢化反应的有效方法，该方法简单且适用于多种底物。该方法基于使用三氟甲磺酸锰盐，其与市售的叔丁醇钾和频哪醇硼烷相结合，可在室温下催化腈、碳酸酯和酯的硼氢化反应，且在不到三小时内产率接近定量。进一步的研究表明，其他储量丰富的金属三氟甲磺酸盐也可以促进该反应，本报告将对此进行进一步讨论。
