Pd-Catalyzed Selective Carbonylative and Non-carbonylative Couplings of Propiolic Acid: One-Pot Synthesis of Diarylalkynones
作者:Wonyoung Kim、Kyungho Park、Ahbyeol Park、Juseok Choe、Sunwoo Lee
DOI:10.1021/ol4004349
日期:2013.4.5
Diarylalkynones were synthesized from one-potPd-catalyzedcarbonylative and noncarbonylative coupling reactions of propiolicacid with aryl iodides under a carbon monoxide atmosphere. Aryl iodide (2.0 equiv), propiolicacid (1.0 equiv), Pd(PPh3)2Cl2 (5 mol %), CuCl (10 mol %), Et3N (6.0 equiv), and CO (8 atm) were reacted under optimized conditions in CH3CN at 80 °C for 1 h. This process afforded
Transition Metal‐Free Synthesis of Substituted Isothiazoles
<i>via</i>
Three‐Component Annulation of Alkynones, Xanthate and NH
<sub>4</sub>
I
作者:Jian Li、Jiaming Li、Xiaoliang Ji、Qiang Liu、Lu Chen、Yubing Huang、Yibiao Li
DOI:10.1002/adsc.202001179
日期:2021.2.16
A protocol was described to access diverse isothiazoles with functionalization potential via transition metal‐free three‐component annulation of alkynones, potassium ethylxanthate (EtOCS2K) and ammonium iodide (NH4I). A sequential regioselective hydroamination/thiocarbonylation/intramolecular cyclizationcascade achieved the efficient formation of consecutive C−N, C−S and N−S bonds in a one‐pot process
Regio- and Stereoselective Hydrosulfonylation of Electron-Deficient Alkynes: Access to Both E- and Z-β-Sulfonyl-α,β-Unsaturated Carbonyl Compounds
作者:Wei Zhang、Gabriel M. Johnson、Zhi Guan、Yan-Hong He
DOI:10.1002/adsc.201801032
日期:2018.12.3
sulfinic acids to access both E‐ and Z‐β‐sulfonyl‐α,β‐unsaturated carbonyl compounds has been developed. We propose that this reaction via a hydroxylallene intermediate delivers the thermodynamically stable E isomer, or via a concerted termolecular AdE3 mechanism affords Z isomer. The stereoselectivity of addition (syn or anti) can be controlled by varying the sulfonyl sources and acidic buffer solutions
已经开发出一种电子不足的炔烃,通过亚磺酸钠或亚磺酸进行无金属的氢磺酰化反应,以同时获得E-和Z - β-磺酰基-α,β-不饱和羰基化合物。我们建议该反应通过羟基丙二烯中间体传递热力学稳定的E异构体,或通过一致的分子Ad E 3机理提供Z异构体。加成的立体选择性(合成或反合成)可以通过改变磺酰基来源和酸性缓冲溶液来控制。该协议展示了内部或末端炔烃的广泛底物范围,包括各种取代的炔酮和炔基酯。这种方法温和,高效,操作简单且易于扩展。
Zinc-catalyzed C–H alkenylation of quinoline <i>N</i>-oxides with ynones: a new strategy towards quinoline-enol scaffolds
作者:Yan Hu、Jiang Nan、Xue Gong、Jiawen Zhang、Jiacheng Yin、Yangmin Ma
DOI:10.1039/d1cc00245g
日期:——
A zinc-catalyzed C–H alkenylation of quinoline N-oxides with ynones has been developed to rapidly assemble a broad collection of valuable quinoline-enol organic architectures.
Transition-metal-free C–C σ-bond activation of α-aryl ketones and subsequent Zn-catalyzed intramolecular cyclization: synthesis of tetrasubstituted furans
作者:Yang Yuan、Hailu Tan、Lingkai Kong、Zhong Zheng、Murong Xu、Jiaqi Huang、Yanzhong Li
DOI:10.1039/c9ob00081j
日期:——
atom-economical protocol for the synthesis of tetrasubstituted furans has been developed. This process is realized through the tandem reactions of Cs2CO3 promoted C–C σ-bond activation of α-aryl ketones followed by Zn-catalyzed intramolecular cyclization. This represents the first example for the preparation of tetrasubstituted furans through rearrangement of molecular skeletons and subsequent transformations
已经开发了用于合成四取代呋喃的高度原子经济的方案。该过程是通过Cs 2 CO 3促进α-芳基酮的C–Cσ键活化,然后进行Zn催化的分子内环化的串联反应来实现的。这代表了通过分子骨架的重排和随后的转化制备四取代呋喃的第一个实例。温和的反应条件和易于获得的起始原料使该方案在有机合成中具有吸引力。