Recyclable and reusable PdCl2(PPh3)2/PEG-2000/H2O system for the carbonylative Sonogashira coupling reaction of aryl iodides with alkynes
作者:Hong Zhao、Mingzhu Cheng、Jiatao Zhang、Mingzhong Cai
DOI:10.1039/c3gc42278j
日期:——
PdCl2(PPh3)2 in a mixture of water and poly(ethylene glycol) (PEG-2000) is shown to be an extremely active catalyst for the carbonylative Sonogashira coupling reaction of aryl iodides with terminal alkynes. The reaction can be conducted under an atmospheric pressure of carbon monoxide at 25 °C with Et3N as a base, yielding a variety of alkynyl ketones in good to excellent yields. Application of this synthetic method to prepare flavones from o-iodophenol and terminal alkynes was also achieved. The isolation of the products is readily achieved by extraction with diethyl ether, and the PdCl2(PPh3)2/PEG-2000/H2O system can be easily recycled and reused six times without any loss of catalytic activity.
Iron(III) Chloride/Diorganyl Diselenides-Promoted Regioselective Cyclization of Alkynyl Aryl Ketones: Synthesis of 3-Organoselenyl Chromenones under Ambient Atmosphere
作者:Benhur Godoi、Adriane Sperança、Cesar A. Bruning、Davi F. Back、Paulo Henrique Menezes、Cristina W. Nogueira、Gilson Zeni
DOI:10.1002/adsc.201100189
日期:2011.8
benign synthesis of 3-organoselenylchromenones was accomplished via iron(III) chloride/diorganyldiselenides-promoted intramolecular 6-endo-dig cyclization of alkynylarylketone derivatives. The cyclization reactions proceeded cleanly under mild reaction conditions, and the desired chromenone derivatives were smoothly isolated in good yields. The methodology proved to be highly regioselective, giving
In the presence of 1-(2-pyridylethynyl)-2-(2-thienylethynyl)benzene as a ligand, the direct synthesis of alkynones has accomplished by a Pd-catalyzed coupling reaction of acid chlorides with terminal acetylenes under mild conditions.
Copper-FreeSonogashira Coupling of Acid Chlorides with Terminal Alkynes in the Presence of a Reusable Palladium Catalyst: An Improved Synthesis of 3-Iodochromenones (=3-Iodo-4H-1-benzopyran-4-ones)
作者:Pravin R. Likhar、M. S. Subhas、Moumita Roy、Sarabindu Roy、M. Lakshmi Kantam
DOI:10.1002/hlca.200890032
日期:2008.2
Pd/C is used as an efficient catalyst for the copper-free Sonogashira coupling of acidchlorides and terminalalkynes to afford ynones in high yields (Tables 1 and 3). Cyclization of (2-methoxyaryl)-substituted ynones induced by I2/ammonium cerium(IV) nitrate (CAN) at room temperature gave 3-iodochromenones (=3-iodo-4H-1-benzopyran-4-ones) in excellent yield (Table 4).
Pd / C用作酰基氯与末端炔烃的无铜Sonogashira偶联的有效催化剂,可高产率提供炔酮(表1和3)。在室温下,由I 2 /硝酸铈(IV)铵(CAN)诱导的(2-甲氧基芳基)取代的炔酮的环化反应得到极好的3-碘代色酮(= 3-碘代-4 H -1-苯并吡喃-4-酮)产量(表4)。