Synthesis of 2-Aryl- and 2,5-Diarylfurans and Thiophenes by Suzuki - Miyaura Reactions Using Potassium Trifluoroborate Salts and Heteroaryltellurides
作者:Giancarlo V. Botteselle、Thomas L. S. Hough、Raphael C. Venturoso、Rodrigo Cella、Adriano S. Vieira、Helio A. Stefani
DOI:10.1071/ch08255
日期:——
The Suzuki–Miyaura cross-coupling reaction of 2-(butyltellanyl) or 2,5-bis-(butyltellanyl)furans and thiophenes with potassium aryltrifluoroborate salts catalyzed by palladium afforded 2-aryl- or 2,5-diaryl-furans and thiophenes in moderate to good yields.
Copper(II)-Promoted, One-Pot Conversion of 1-Alkynes with Anhydrides or Primary Amines to the Respective 2,5-Disubstituted Furans or Pyrroles under Microwave Irradiation Conditions
作者:Hyejeong Lee、Yeonhui Yi、Chul-Ho Jun
DOI:10.1002/adsc.201500711
日期:2015.11.16
Furans and pyrroles are prepared from 1-alkynes by using a Cu(II)-promoted, one-pot, microwaveirradiation method. Glaser coupling of 1-alkynes and cyclization of the resulting 1,3-diyne in the presence of an anhydride or a primaryamine results in the formation of the respective 2,5-diaryl- or 2,5-dialkyl-substituted furans and pyrroles.
A highlyefficientsynthesis of a wide range of 2,5-disubstituted furans from enyne acetates is described. The reactions are conducted by using Lewis acid and palladiumcatalyst and provide symmetrical and unsymmetrical products in good to excellent yields, with broad substrate scope, including a variety of aromatic and aliphatic substituents in the 2- and 5-position of the furan ring.
Aryl(triethyl)silanes are found to undergo cross‐coupling with iodoarenes in the presence of catalytic amounts of CuBr2 and Ph‐Davephos, as well as cesium fluoride as a stoichiometric base. Because the silicon reagents are readily accessible through catalytic C−H silylation of aromatic substrates, the net transformation allows coupling of aromatic hydrocarbons with iodoarenes via triethylsilylation
Sequential Synthesis of Furans from Alkynes: Successive Ruthenium(II)- and Copper(II)-Catalyzed Processes
作者:Min Zhang、Huan-Feng Jiang、Helfried Neumann、Matthias Beller、Pierre H. Dixneuf
DOI:10.1002/anie.200805531
日期:——
5‐Disubstituted furans can be prepared from terminal alkynes in one pot using two successive catalytic reactions (see scheme; p‐TSA=para‐toluenesulfonic acid). First, a 1,3‐dienyl alkyl ether is produced by the dimerization of a terminal alkyne and addition of an alcohol catalyzed by [RuCp*(NCMe)3][PF6]. Then, consecutive hydrolysis and cyclization catalyzed by CuCl2 provides the 2,5‐disubstituted furan.