Iridium-Catalyzed sp<sup>3</sup> C–H Borylation in Hydrocarbon Solvent Enabled by 2,2′-Dipyridylarylmethane Ligands
作者:Margaret R. Jones、Caleb D. Fast、Nathan D. Schley
DOI:10.1021/jacs.0c00524
日期:2020.4.8
Iridium-catalyzed alkane C-H borylation has long suffered from poor atom economy, resulting both from inclusion of only a single boron equivalent from the diboron reagent and a requirement for neat substrate. Appropriately-substituted dipyridylarylmethane ligands are found to give highly active alkane borylation catalysts which facilitate C-H borylation with improved conversion efficiency. This system provides for
铱催化的烷烃 CH 硼酸化长期以来一直受到原子经济性差的影响,这既是由于只包含来自二硼试剂的单一硼等价物,又是对纯底物的要求。发现适当取代的二吡啶基芳基甲烷配体提供高活性烷烃硼化催化剂,其促进 CH 硼化并提高转化效率。该系统提供完全消耗二硼试剂,在低催化剂负载下产生两摩尔当量的产物。该系统的卓越功效还能够在烃溶剂中对未活化的烷烃进行硼化反应,从而减少过量底物并改善官能团兼容性。该配体的有效性通过一系列官能团显示出来,在纯底物的传统硼酸化条件下和在环己烷溶剂中的非典型条件下。这种催化系统的效用通过含有极性官能团的底物的硼化反应来举例说明,这些底物在纯条件下对 CH 硼酸化反应不起反应。