Department of Chemistry, Scripps Research, La Jolla, CA, USA.
Asymchem Life Science (Tianjin) Co., Ltd, Tianjin, P.R. China.
Nat Chem. 2021 Apr;13(4):367-372. doi: 10.1038/s41557-021-00640-2. Epub 2021 Mar 23.
Electrochemical techniques have long been heralded for their innate sustainability as efficient methods to achieve redox reactions. Carbonyl desaturation, as a fundamental organic oxidation, is an oft-employed transformation to unlock adjacent reactivity through the formal removal of two hydrogen atoms. To date, the most reliable methods to achieve this seemingly trivial reaction rely on transition metals (Pd or Cu) or stoichiometric reagents based on I, Br, Se or S. Here we report an operationally simple pathway to access such structures from enol silanes and phosphates using electrons as the primary reagent. This electrochemically driven desaturation exhibits a broad scope across an array of carbonyl derivatives, is easily scalable (1-100 g) and can be predictably implemented into synthetic pathways using experimentally or computationally derived NMR shifts. Systematic comparisons to state-of-the-art techniques reveal that this method can uniquely desaturate a wide array of carbonyl groups. Mechanistic interrogation suggests a radical-based reaction pathway.
电化学技术因其作为有效实现氧化还原反应的方法而具有内在的可持续性，长期以来一直备受关注。羰基去饱和作用作为一种基本的有机氧化反应，是一种常用的转化方法，通过形式上除去两个氢原子来打开相邻的反应性。迄今为止，实现这一看似简单反应的最可靠方法依赖于过渡金属（Pd 或 Cu）或基于 I、Br、Se 或 S 的化学计量试剂。在这里，我们报告了一种从烯醇硅烷和膦酸盐中获得此类结构的操作简单的途径，该途径使用电子作为主要试剂。这种电化学驱动的去饱和作用在一系列羰基衍生物中具有广泛的适用性，易于规模化（1-100g），并且可以使用实验或计算得出的 NMR 位移来预测性地纳入合成途径。与最先进技术的系统比较表明，该方法可以独特地使各种羰基去饱和。机理研究表明这是一种基于自由基的反应途径。
