A highly site-selective acyloxylation of stable enamines with PhI(OAc)2 under metal-free conditions to afford (E)-vinyl acetate derivatives in good to excellent yields is described. Depending on the judicious choice of the solvent system, either the α- or β-site-selective product could be obtained with high selectivity. For the α-site-selective product, the rearranged amide compound is obtained as
An expedient [5 + 1] annulation method via Rh(III)-catalyzed C–H bond functionalization of enaminones to synthesize polyaromatic rings is described. The reaction tolerates a broad range of functional groups and offers a new entry to construct polycyclic aromatic compounds with amino and formyl substituents. A possible reaction mechanism was proposed based on the results obtained from isotope labeling
Tunable and Diastereoselective Brønsted Acid Catalyzed Synthesis of β-Enaminones
作者:Ye-Won Kang、Yu Jin Cho、Seung Jin Han、Hye-Young Jang
DOI:10.1021/acs.orglett.5b03445
日期:2016.1.15
The Brønsted acid catalyzed Meyer–Schuster reaction of hemiaminals was studied for the stereoselective synthesis of β-enaminones. Hemiaminals were formed from propargyl aldehydes (or the oxidation of propargyl alcohols) and amines in the presence of Brønsted acids. A critical step to control the stereochemistry of the products is the protonation of the corresponding allenol intermediate, which is dictated
Visible Light-Induced Thiocyanation of Enaminone C–H Bond to Access Polyfunctionalized Alkenes and Thiocyano Chromones
作者:Yong Gao、Yunyun Liu、Jie-Ping Wan
DOI:10.1021/acs.joc.8b02981
日期:2019.2.15
The visiblelightinducedC–H bond thiocyanation on the α-site of tertiary enaminones has been realized under metal-free, photocatalytic conditions in the presence of Rose Bengal, which enables the synthesis of thiocyanated alkene derivatives and chromones using NH4SCN as the thiocyano source under an aerobic atmosphere. In addition, employing Ru(bpy)3Cl2·6H2O as the photocatalyst switches the reaction
Silver-catalyzed efficient synthesis of enaminones from propargyl alcohols and amines
作者:Mengshun Li、Dongmei Fang、Feng Geng、Xianping Dai
DOI:10.1016/j.tetlet.2017.09.054
日期:2017.12
Enaminones are used as the key intermediates to construct heterocyclic compounds with various bioactivities. In this study, a simple and efficient approach for the synthesis of enaminones via amination of propargyl alcohols was developed. Under the catalysis of Ag2CO3, the reaction proceeded smoothly to afford the desired products in good yields. Preliminary mechanism experiments showed that Ag2CO3
烯胺酮用作构建具有各种生物活性的杂环化合物的关键中间体。在这项研究中,开发了一种通过炔丙醇胺化合成烯胺酮的简单有效的方法。在Ag 2 CO 3的催化下,反应顺利进行,以高收率得到所需产物。初步的机理实验表明,Ag 2 CO 3在反应过程中起着至关重要的作用。