Synthesis of 2-Substituted Quinolines from 2-Aminostyryl Ketones Using Iodide as a Catalyst
作者:So Young Lee、Jiye Jeon、Cheol-Hong Cheon
DOI:10.1021/acs.joc.8b00552
日期:2018.5.4
A new protocol for the synthesis of 2-substituted quinolinesfrom 2-aminostyryl ketones has been developed using iodide as a nucleophilic catalyst. Conjugate addition of iodide to 2-aminostyryl ketones yielded the corresponding β-iodoketones, which could have a conformation where the amino and carbonyl groups are proximal through free rotation about the Cα–Cβ single bond. Subsequent condensation between
On-Water Synthesis of 2-Substituted Quinolines from 2-Aminochalcones Using Benzylamine as the Nucleophilic Catalyst
作者:So Young Lee、Cheol-Hong Cheon
DOI:10.1021/acs.joc.8b01675
日期:2018.11.2
On-water synthesis of 2-substituted quinolines from 2-aminochalcone derivatives was developed using benzylamine as the nucleophilic catalyst. Various 2-aminochalcones could be applied to this protocol, and the desired 2-substituted quinoline products were isolated in excellent yields by simple filtration. Furthermore, we elucidated the role of benzylamine in this transformation and provided the detailed
derivatives containing three stereocenters were prepared via one-step synthesis in yields ranging from 88 to 96% and in enantioselectivities (enantiomeric excess (ee)) ranging from 85 to 97%, with diastereoselectivities of approximately 14/2/1. Therefore, this method provides an efficientroute for the synthesis of a new class of opticallyactive 2-spirobenzothiophenones.
本报告描述了在金鸡纳生物碱胺存在下2-亚烷基苯并[ b ]噻吩酮衍生物与烯酮之间的有机催化级联反应。通过一步合成,制备了包含三个立体中心的螺苯并噻吩苯甲酸环己烷衍生物,其产率为88%至96%,对映选择性(对映体过量(ee))为85至97%,非对映选择性约为14/2/1。因此,该方法为合成新型的光学活性的2-螺苯并噻吩酮提供了有效的途径。
PPh<sub>3</sub>⋅HBr-DMSO Mediated Expedient Synthesis of γ-Substituted β,γ-Unsaturated α-Ketomethylthioesters and α-Bromo Enals: Application to the Synthesis of 2-Methylsulfanyl-3(<i>2 H</i>)-furanones
作者:Kanchan Mal、Abhinandan Sharma、Prakas R. Maulik、Indrajit Das
DOI:10.1002/chem.201303755
日期:2014.1.13
An efficient chemoselective general procedure for the synthesis of γ‐substituted β,γ‐unsaturatedα‐ketomethylthioesters from α,β‐unsaturatedketones has been achieved through an unprecedented PPh3⋅HBr‐DMSO mediated oxidative bromination and Kornblum oxidation sequence. The newly developed reagent system serves admirably for the synthesis of α‐bromoenals from enals. Furthermore, AuCl3‐catalyzed efficient
A blue-light-promoted carbon-carbon double bondisomerization in the absence of any photoredox catalyst is reported. It provides rapid access to a series of quinolines in good to excellent yields under simple aerobic conditions. The protocol is direct, catalyst-free and operationally convenient.