Intramolecular Reactions of Metal Carbenoids with Allylic Ethers: Is a Free Ylide Involved in Every Case?
作者:J. Stephen Clark、K. Emelie Hansen
DOI:10.1002/chem.201304054
日期:2014.4.25
reactions of the 13C‐labelled diazo carbonyl substrates 18* and 19* were performed. Results obtained from copper‐ and iridium‐catalyzed reactions of the 13C‐labelled α‐diazo β‐keto ester 19* indicate that either or both of these reactions do not proceed via a free oxonium ylide but instead follow a competing non‐ylide route that delivers apparent [2,3]‐sigmatropic rearrangement products. In the case
进行13 C标记的重氮羰基18 *和19 *的铑,铜和铱催化的反应。从13 C标记的α-重氮β-酮酯19 *的铜和铱催化反应获得的结果表明,这些反应中的任何一个或两个都不通过游离的叶立德叶立德进行,而是遵循竞争性的非叶立德路线提供明显的[2,3]-σ重排产物。在铱催化的α-重氮β-酮酸酯19 *的情况下交叉实验获得的结果表明,最初形成的与金属结合的叶立德解离生成铱烯醇盐和烯丙基阳离子,它们重组形成CC键。