141778-52-1Relevant articles and documents
Aversatile palladium/triphosphane system for direct arylation of heteroarenes with chloroarenes at low catalyst loading
Roy, David,Mom, Sophal,Beauperin, Matthieu,Doucet, Henri,Hierso, Jean-Cyrille
supporting information; experimental part, p. 6650 - 6654 (2010/12/25)
Put a ring on it: The use of an air-stable, robust palladium/tridentate phosphane catalyst in direct C-H and C-Cl activation reactions is reported (see scheme; DMAc=N,N-dimethylacetamide, TBAB=tetra-n-butylammonium bromide). Electron-rich, electron-poor, and polysubstituted furans (X=O), thiophenes (X=S), pyrroles (X=NR5), and thiazoles were arylated with chloroarenes in the presence of the catalyst.
Ligand-less palladium-catalyzed direct 5-arylation of thiophenes at low catalyst loadings
Roger, Julien,Pozgan, Franc,Doucet, Henri
experimental part, p. 425 - 432 (2010/04/22)
Ligand-less Pd(OAc)2 provides a very efficient catalyst for the direct 5-arylation of thiophene derivatives. With this catalyst, a low palladium concentration (0.1-0.001 mol%) should be employed in order to obtain high yields of coupling products. At higher concentrations a fast formation of inactive "Pd black" generally occurs. Substrates/catalysts ratios up to 100000 can be employed with the most reactive aryl bromides. A very wide variety of functional groups is tolerated on both coupling partners. The major waste of this reaction is HBr associated with KOAc. Therefore this procedure is more economically and environmentally attractive than the traditional cross-coupling procedures employing organometallic derivatives.
New Liquid Crystalline Compounds Based on Thiophene
Brettle, Roger,Dunmur, David A.,Marson, Charles M.,Pinol, Milagros,Toriyama, Kazuhisa
, p. 613 - 616 (2007/10/02)
A homologous series of 2-alkyl-5-(4'-cyanophenyl)thiophenes has been prepared and shown to have improved properties for use in liquid crystal displays.The thiophene ring is prepared from a 1-(4'-bromophenyl)-1,4-dioxoalkane, constructed using the Stetter procedure, by the action of Lawessons reagent, and the cyano-group is finally introduced using a copper(I)-mediated exchange reaction.