通过Cu II / B 2 pin 2催化的二氟烷基溴与的反应,开发了一种有效且通用的醛衍生的C(sp 2)-H二氟烷基化方法。在该反应中,芳族和脂族二氟烷基化醛衍生的azo均可以良好至优异的产率获得。对于某些杂芳族醛衍生的azo,可以将两种氟乙酸酯引入最终产物中。初步的机理研究表明,通过SET途径的二氟烷基自由基参与了反应。另外,催化二硼试剂在该转化中起着不可或缺的作用。
Gold-Catalyzed Highly Selective Photoredox C(sp<sup>2</sup>
)−H Difluoroalkylation and Perfluoroalkylation of Hydrazones
作者:Jin Xie、Tuo Zhang、Fei Chen、Nina Mehrkens、Frank Rominger、Matthias Rudolph、A. Stephen K. Hashmi
DOI:10.1002/anie.201508622
日期:2016.2.18
hydrazones are highly functionalized, versatile molecules. A mild reduction of the coupling products can efficiently produce gem‐difluoromethylated β‐amino phosphonic acids and β‐amino acid derivatives. In mechanistic studies, a difluoroalkyl radical intermediate was detected by an EPR spin‐trappingexperiment, indicating that a gold‐catalyzed radical pathway is operating.
据报道,使用容易获得的R F -Br试剂,gold的金催化光氧化还原C(sp 2)-H二氟烷基化和hydr的全氟烷基化。所得的宝石二氟甲基化和全氟烷基化的azo是高度官能化的多用途分子。偶合产物的轻度减少可以有效地生产出宝石-二氟甲基化的β-氨基膦酸和β-氨基酸衍生物。在机理研究中,通过EPR自旋捕获实验检测到二氟烷基自由基中间体,表明金催化的自由基途径正在起作用。
Dioxygen-Triggered Oxo-Sulfonylation of Hydrazones
A simple and highly efficient method for the oxo-sulfonylation of aldehyde-derived hydrazones has been developed using sulfinic acid as a source of sulfonyl group and oxygen as a green oxidant under metal-free conditions at room temperature. The present C–O and N–S bond-forming difunctionalization strategy affords diversely functionalized N-acylsulfonamides in good yield. Experimental results suggest
Reaction of the lithio-derivative of methoxyallene with hydrazones. Part 2: Formation of 3-pyrrolines and azetidines; synthetic and mechanistic aspects
作者:Valérie Breuil-Desvergnes、Jacques Goré
DOI:10.1016/s0040-4020(01)00031-x
日期:2001.3
3-pyrrolines when the time and temperature of the reaction are increased, but the rate of this transformation depends on the substituents of the terminal nitrogen. A reaction mechanism is proposed which involves intermolecular or intramolecular electron transfers from the lithium amide leading to hydrazinyl radicals. The relative stabilities of these intermediates may then explain the role of the substituents
Electrochemical Oxidative C(sp<sup>2</sup>)–H Amination of Aldehyde Hydrazones with Azoles
作者:Zhi-Mei Fu、Jian-Shan Ye、Jing-Mei Huang
DOI:10.1021/acs.orglett.2c01782
日期:2022.8.19
A general and highly efficient method for the electrochemical C(sp2)–Hamination of aldehyde hydrazones with azoles has been developed. This reaction proceeds under exogenous metal-, catalyst-, and oxidant-free conditions to provide aminated hydrazone derivatives in good to excellent yields. This strategy applies to both aromatic and aliphatic aldehyde hydrazones and tolerates a broad range of functional
We have developed an electrochemical method for the direct C–H sulfonylation of aldehyde hydrazones using sodium sufinates as the sulfonylating agent under supporting electrolyte-free conditions. This straightforward sulfonylation strategy afforded a library of (E)-sufonylated hydrazones with high tolerance of various functional groups. The radical pathway of this reaction has been revealed by the
我们开发了一种电化学方法,用于在无支持电解质条件下使用亚磺酸钠作为磺酰化剂对醛腙进行直接 C-H 磺酰化。这种直接的磺酰化策略提供了一个对各种官能团具有高耐受性的 ( E )-磺酰化腙库。机理研究揭示了该反应的激进途径。