C−O coupling of Malonyl Peroxides with Enol Ethers
<i>via</i>
[5+2] Cycloaddition: Non‐Rubottom Oxidation
作者:Vera A. Vil'、Evgenii S. Gorlov、Oleg V. Bityukov、Yana A. Barsegyan、Yulia E. Romanova、Valentina M. Merkulova、Alexander O. Terent'ev
DOI:10.1002/adsc.201900271
日期:2019.7.2
Malonyl peroxides act both as oxidants and reagents for C−O coupling in reactions with methyl and silyl enol ethers. In the proposed conditions, the oxidative C−O coupling of malonyl peroxides with enol ethers selectively proceeds, bypassing the traditional Rubottom hydroxylation of enol ethers by peroxides. It was observed that the oxidative [5+2] cycloaddition of malonyl peroxides and enol ethers
丙二酰过氧化物在与甲基和甲硅烷基烯醇醚的反应中既充当氧化剂,又充当用于C-O偶联的试剂。在提出的条件下,丙二酰过氧化物与烯醇醚的氧化C-O偶联选择性进行,绕过了过氧化物对烯醇醚的传统Rubottom羟化反应。观察到过氧化丙二酰和烯醇醚的氧化[5 + 2]环加成反应是发现过程的关键阶段。甲硅烷基烯醇醚的氧化C-O偶联导致形成带有游离羧酸基团的α-酰氧基酮。专门开发的制备式一锅法可通过甲硅烷基烯醇醚的形成以及随后的偶联成α-酰氧基酮,收率35-88%。酸催化的与甲基烯醇醚的偶联产生了出色的产物,同时保留了易于氧化的烯醇片段。此外,这些分子含有一个游离的羧酸基团,因此这些非平凡的产物含有两个通常不相容的酸和烯醇醚基团。