1357381-89-5Relevant academic research and scientific papers
Cascade Synthesis of 4-Arylcoumarins: Pd-Catalyzed Arylations and Cyclizations with (E)-Ethyl 3-(2-Hydroxyaryl)acrylates and Triarylantimony Difluorides
Kitamura, Yuki,Matsumura, Mio,Kato, Yukari,Murata, Yuki,Yasuike, Shuji
supporting information, p. 1652 - 1657 (2020/03/05)
Herein, we describe a simple general method for the synthesis of 4-arylcoumarins using pentavalent organoantimony compounds. The reactions of 3-(2-hydroxyaryl)acrylates with triarylantimony difluorides in the presence of Pd(OAc)2 (10 mol-%) and 2,2'-bipyridyl (10 mol-%) at 80 °C under aerobic conditions afforded 4-arylcoumarins in good-to-excellent yields. This protocol involves a cascade oxidative Heck-type arylation followed by cyclization, with all the aryl groups in the triarylantimony difluoride transferred to the coupling products. Triarylantimony difluorides resulted in better outcomes than those obtained with other pentavalent organoantimony or bismuth compounds.
Heck and oxidative boron Heck reactions employing Pd(II) supported amphiphilized polyethyleneimine-functionalized MCM-41 (MCM-41@aPEI-Pd) as an efficient and recyclable nanocatalyst
Motevalizadeh, Seyed Farshad,Alipour, Masoumeh,Ashori, Fatemeh,Samzadeh-Kermani, Alireza,Hamadi, Hosein,Ganjali, Mohammad Reza,Aghahosseini, Hamideh,Ramazani, Ali,Khoobi, Mehdi,Gholibegloo, Elham
, (2017/10/23)
A novel nanocatalyst was developed based on covalent surface functionalization of MCM-41 with polyethyleneimine (PEI) using [3-(2,3-Epoxypropoxy)propyl] trimethoxysilane (EPO) as a cross-linker. Amine functional groups on the surface of MCM-41 were then conjugated with iodododecane to render an amphiphilic property to the catalyst. Palladium (II) was finally immobilized onto the MCM-41@PEI-dodecane and the resulted MCM-41@aPEI-Pd nanocatalyst was characterized by FT-IR, TEM, ICP-AES and XPS. Our designed nanocatalyst with a distinguished core-shell structure and Pd2+ ions as catalytic centers was explored as an efficient and recyclable catalyst for Heck and oxidative boron Heck coupling reactions. In Heck coupling reaction, the catalytic activity of MCM-41@aPEI-Pd in the presence of triethylamine as base led to very high yields and selectivity. Meanwhile, the MCM-41@aPEI-Pd as the first semi-heterogeneous palladium catalyst was examined in the C-4 regioselective arylation of coumarin via the direct C-H activation and the moderate to excellent yields were obtained toward different functional groups. Leaching test indicated the high stability of palladium on the surface of MCM-41@aPEI-Pd as it could be recycled for several runs without significant loss of its catalytic activity.
Rh-Catalyzed Synthesis of Coumarin Derivatives from Phenolic Acetates and Acrylates via C-H Bond Activation
Gadakh, Sunita K.,Dey, Soumen,Sudalai, Arumugam
, p. 11544 - 11550 (2015/12/04)
An efficient annulation strategy involving the reaction of phenolic acetates with acrylates in the presence of [Rh2(OAc)4] as catalyst and formic acid as reducing agent, leading to the high yield synthesis of coumarin derivatives, has been developed. The addition of NaOAc as a base increased the yield of the products. The reaction is quite successful for both electron-rich as well as electron-deficient phenolic acetates, affording coumarins with excellent regioselectivity, and proceeds via C-H bond activation proven by deuterium incorporation studies.
Palladium-catalyzed domino protodecarboxylation/oxidative Heck reaction: Regioselective arylation of coumarin-3-carboxylic acids
Khoobi, Mehdi,Molaverdi, Fatemeh,Alipour, Masoumeh,Jafarpour, Farnaz,Foroumadi, Alireza,Shafiee, Abbas
, p. 11164 - 11168 (2014/01/06)
A protocol for straightforward and step-economical synthesis of neoflavones from coumarin-3-carboxylic acids is developed. This approach enables controlled protodecarboxylation/regioselective C-H arylation of coumain-3-carboxylic acids in one-pot using a
A facile route to flavone and neoflavone backbones via a regioselective palladium catalyzed oxidative Heck reaction
Khoobi, Mehdi,Alipour, Masoumeh,Zarei, Samaneh,Jafarpour, Farnaz,Shafiee, Abbas
supporting information; experimental part, p. 2985 - 2987 (2012/04/04)
A straightforward and atom-economical base-free palladium-catalyzed regioselective direct arylation of coumarins and chromenones is devised. This protocol is compatible with a wide variety of electron-donating and -withdrawing substituents and allows construction of various biologically important flavone and neoflavone backbones.
Palladium-catalyzed oxidative heck coupling reaction for direct synthesis of 4-arylcoumarins using coumarins and arylboronic acids
Li, Yaming,Qi, Zisong,Wang, Huifeng,Fu, Xinmei,Duan, Chunying
supporting information; experimental part, p. 2053 - 2057 (2012/04/04)
An efficient protocol for the direct synthesis of 4-arylcoumarins via palladium-catalyzed oxidative Heck coupling reaction of coumarins and arylboronic acids was developed. 4-Arylcoumarins were obtained in moderate to excellent yields, and the reaction also showed tolerance toward functional groups such as hydro, methoxy, diethylamino, nitro, and chloro groups.
