A Rh(III)-catalyzed highly efficient C6-alkylation of 2-pyridones has been achieved successfully with α-diazo carbonyl compounds. The developed method is simple, mild, and highly regioselective with a broad range of substrate scope. The regioselectivity is guided by the pyridyl substituent attached to the nitrogen center of the pyridone ring. The directing group can be easily removed, and the only
Rh2(OAc)4-catalyzed 2,3-migration of β-ferrocenecarboxyl α-diazocarbonyl compounds: an efficient synthesis of ferrocene-containing α,β-unsaturated esters
作者:Shufeng Chen、Yan Du、Haiying Zhao、Baoguo Li
DOI:10.1039/c3ra48071b
日期:——
A series of β-ferrocenecarboxyl α-diazocarbonyl compounds were prepared by the reaction of ferrocenoyl chloride with β-hydroxyl α-diazocarbonyl compounds in the presence of pyridine. The diazo decomposition of these ferrocene-containing diazocarbonyl compounds with Rh2(OAc)4 resulted in 2,3-ferrocenecarboxyl migration to give ferrocene-containing α,β-unsaturated esters in high yields.
Herein, a de novo vinylogous reactivity of vinyl diazo esters in the C–H bond allylation of benzamides has been developed by coalescing cobalt and photoredox catalysis via C–H activation/allyl carbene migratory insertion. A close relationship between the high valent cobalt catalyst and the photocatalyst has been found to be crucial for this reactivity. The reaction uses oxygen as the sole oxidant and
B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>-Catalyzed Diastereoselective and Divergent Reactions of Vinyldiazo Esters with Nitrones: Synthesis of Highly Functionalized Diazo Compounds
作者:Katarina Stefkova、Michael G. Guerzoni、Yara van Ingen、Emma Richards、Rebecca L. Melen
DOI:10.1021/acs.orglett.2c04198
日期:2023.1.27
transition-metal-free, highlydiastereoselectiveLewisacid catalyzed methodology toward the synthesis of isoxazolidine-based diazo compounds from the reaction between vinyldiazo esters and nitrones. Interestingly, the isoxazolidine products were identified to have contrasting diastereoselectivity to previously reported metal-catalyzed reactions. Furthermore, the same catalyst can be used with enol
在此,我们报告了一种温和的、不含过渡金属的、高度非对映选择性的路易斯酸催化方法,用于通过乙烯基重氮酯和硝酮之间的反应合成基于异恶唑烷的重氮化合物。有趣的是,异恶唑烷产物被认为具有与先前报道的金属催化反应相反的非对映选择性。此外,相同的催化剂可以与烯醇重氮酯一起使用,促进Mukaiyama-Mannich产物的形成。然后这些重氮产物可以进一步官能化以提供苯并[ b ]氮杂卓和吡咯烷酮衍生物。
Photoredox‐Enabled Self‐(3+2) Cyclization of Vinyldiazo Reagents: Synthesis of Cyclopentenyl <i>α</i>‐Diazo Compounds
作者:Weiyu Li、Sen Li、Claire Empel、Rene M. Koenigs、Lei Zhou
DOI:10.1002/anie.202309947
日期:2023.10.16
A novel self-(3+2) cycloaddition of vinyldiazo compounds is described, providing cyclopentene derivatives with conservation of one diazo functional group. The reaction involves an unprecedented single electron oxidation of vinyldiazo compounds using iridium photocatalysis.