range of readily available α-phosphateenamides were subjected to (hetero)aromatic dioxazaborocanes (DABO boronates), providing the desired α-functionalized enamides in high yields via palladium-catalyzed cross-coupling reactions. Notably, the reaction proceeds in the presence of a slight excess of boron derivatives and tolerates cyclic, nonaromatic and/or electron-rich enamides.
Electrochemically driven desaturation of carbonyl compounds
作者:Samer Gnaim、Yusuke Takahira、Henrik R. Wilke、Zhen Yao、Jinjun Li、Dominique Delbrayelle、Pierre-Georges Echeverria、Julien C. Vantourout、Phil S. Baran
DOI:10.1038/s41557-021-00640-2
日期:2021.4
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
长期以来,电化学技术因其与生俱来的可持续性而被誉为实现氧化还原反应的有效方法。作为一种基本的有机氧化,羰基去饱和是一种常用的转化方法,通过正式去除两个氢原子来解锁相邻的反应性。迄今为止,实现这种看似微不足道的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,我们报告了一种操作简单的途径,可以从烯醇硅烷和以电子为主要试剂的磷酸盐。这种电化学驱动的去饱和在一系列羰基衍生物中表现出广泛的范围,易于扩展(1-100 g),并且可以使用实验或计算得出的 NMR 位移可预测地实施到合成途径中。与最先进技术的系统比较表明,这种方法可以独特地使各种羰基去饱和。机械审讯表明基于自由基的反应途径。
New Synthetic Approach to Cyclopenta-Fused Heterocycles Based upon a Mild Nazarov Reaction
作者:Ernesto G. Occhiato、Cristina Prandi、Alessandro Ferrali、Antonio Guarna、Paolo Venturello
DOI:10.1021/jo034939p
日期:2003.12.1
role in forcing the conrotatory process to take place in one sense only: allowing the synthesis of diastereomerically pure compounds to be realized. Because different patterns of substitution on the heterocycle are compatible with the reaction conditions, the methodology developed could be very useful for the synthesis of natural products and biologically active compounds containing cyclopenta-fused O-