Palladium catalyzed Heck-arylation/cyclization cascade: An environmentally benign and efficient synthesis of 4-arylcoumarins in water
作者:Junmin Chen、Wei Liu、Liandi Zhou、Yongli Zhao
DOI:10.1016/j.tetlet.2018.05.032
日期:2018.6
An environmentally benign and efficient approach for the synthesis of 4-arylcoumarins from ortho-hydroxy cinnamate ester derivatives with aryl iodides was developed in water under aerobic conditions. This transformation proceeds through a palladiumcatalyzed Heck-arylation/cyclization cascade reaction. The present protocol features a wide substrate scope and readily available starting materials to
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.
Pd-catalyzed chemo-selective mono-arylations and bis-arylations of functionalized 4-chlorocoumarins with triarylbismuths as threefold arylating reagents
作者:Maddali L.N. Rao、Abhijeet Kumar
DOI:10.1016/j.tet.2014.07.059
日期:2014.9
4-chlorocoumarins were studied under palladium catalysis usingtriarylbismuths as threefoldarylatingreagents. The high reactivity of 4-chlorocoumarins was demonstrated delivering mono- and bis-arylation products in a chemo-selective manner. The reaction conditions employed are simple, robust and the threefold coupling reactivity of triarylbismuthreagents was witnessed with good to high yields in 2–4 h conditions
A versatile palladium catalyst system for Suzuki–Miyaura coupling of alkenyl tosylates and mesylates
作者:Pui Yu Wong、Wing Kin Chow、Kin Ho Chung、Chau Ming So、Chak Po Lau、Fuk Yee Kwong
DOI:10.1039/c1cc12240a
日期:——
A general and effectivepalladium system for Suzuki-Miyaura coupling of alkenyl electrophiles under mild reaction conditions is reported. With the Pd(OAc)(2)/CM-phos system, a variety of alkenyltosylates are coupled well with ArB(OH)(2). Moreover, the first successful examples of using alkenyl mesylates in alkenylation are also described.
Rh(I)-catalyzed cross-coupling reactions of alkenyl tosylates with potassium aryltrifluoroborates
作者:Jie Wu、Liang Zhang、Yong Luo
DOI:10.1016/j.tetlet.2006.07.085
日期:2006.9
RhCl(PPh3)3/DPPF was successfully employed as an efficient catalyst in the Suzuki–Miyaura cross-coupling reactions of potassium aryltrifluoroborates with alkenyl tosylates, affording the corresponding products in good to excellent yields.