Ligand-less palladium-catalyzed direct 5-arylation of thiophenes at low catalyst loadings
作者:Julien Roger、Franc Požgan、Henri Doucet
DOI:10.1039/b819912d
日期:——
Ligand-less Pd(OAc)2 provides a very efficient catalyst for the direct5-arylation of thiophenederivatives. 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
Direct Pd-Catalyzed Cross-Coupling of Functionalized Organoaluminum Reagents
作者:Klaus Groll、Tobias D. Blümke、Andreas Unsinn、Diana Haas、Paul Knochel
DOI:10.1002/anie.201205987
日期:2012.10.29
A handsome couple: Through the use of the simple Pd catalyst [Pd(tmpp)2Cl2] (tmpp=tris(2,4,6‐trimethoxyphenyl)phosphine) and THF/DMF as solvent, various aryl‐, heteroaryl‐, benzyl‐ and alkylaluminum reagents can be readily cross‐coupled with aryl or heteroaryl iodides, bromides, and nonaflates, and in special cases even with chlorides and triflates. This cross‐coupling tolerates free NH2 groups, aldehydes