A novel organozinc reagent 4-coumarinylzinc bromide; preparation and application in the synthesis of 4-substituted coumarin derivatives
作者:Reuben D. Rieke、Seung-Hoi Kim
DOI:10.1016/j.tetlet.2011.03.151
日期:2011.6
A novel organozinc reagent, 4-coumarinylzinc bromide, was prepared by the direct oxidative addition of active zinc to 4-bromocoumarin. The resulting organozinc bromide underwent the palladium-catalyzed cross-coupling reactions with a variety of aryl halides and acid chlorides affording the corresponding coupling products in good yields under mild conditions.
Nickel-catalyzed cross-coupling of β-carbonyl alkenyl pivalates with arylzinc chlorides
作者:Wen-Jing Pan、Zhong-Xia Wang
DOI:10.1039/c7ob02947k
日期:——
The nickel-catalyzed cross-coupling reaction of β-carbonyl alkenyl pivalates with arylzinc reagents generates 3-aryl-substituted α,β-unsaturated carbonyl compounds via C–O bond cleavage. The reaction features mild reaction conditions, a wide scope of substrates, and good functional group tolerance.
Synthesis of 4-arylcoumarins via palladium-catalyzed arylation/cyclization of ortho-hydroxylcinnamates with diaryliodonium salts
作者:Yang Yang、Jianwei Han、Xunshen Wu、Shujia Xu、Limin Wang
DOI:10.1016/j.tetlet.2015.04.082
日期:2015.6
ortho-hydroxylcinnamate ester derivatives by using diaryliodonium(III) salts has been developed. With this method, 4-arylcoumarins were easily prepared in good to excellent yields under base-free conditions. Additionally, this protocol provided an efficient alternative for the preparation of related 4-arylated coumarin compounds which are useful in the access to 5-lipoxygenaseinhibitors.
[Pd(PPh3)2(saccharinate)2]—general catalyst for Suzuki–Miyaura, Negishi cross-coupling and C–H bond functionalization of coumaryl and pyrone substrates
作者:Parin Shah、M. Dolores Santana、Joaquín García、J. Luis Serrano、Minal Naik、Suhas Pednekar、Anant R. Kapdi
DOI:10.1016/j.tet.2012.12.030
日期:2013.2
The potential of complex [Pd(PPh3)(2)(saccharinate)(2)] 1 in catalyzing Suzuki-Miyaura cross-coupling of 4-halo and 4-bromomethyl coumaryl and pyrone substrates with different aryl boronic acids has been explored. Excellent yields of the desired products are obtained in competitive reaction time and under relatively mild conditions. Negishi cross-coupling of 4-coumaryl tosylate with aryl and allcylzinc reagents has also been performed with good yields of the cross-coupled products obtained in most cases. Intramolecular C-H bond functionalization of coumaryl ethers also furnished very high yields of synthetically attractive tetracyclic ring systems exhibiting the potential of I as a powerful catalyst in synthetically important reactions. (C) 2012 Elsevier Ltd. All rights reserved.
Nickel-Catalyzed Cross-Couplings of 4-Diethylphosphonooxycoumarins with Organozinc Reagents: An Efficient New Methodology for the Synthesis of 4-Substituted Coumarins