Department of Chemistry, Room 18-490, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Angew Chem Int Ed Engl. 2012 May 7;51(19):4710-3. doi: 10.1002/anie.201201244. Epub 2012 Mar 30.
[Image: see text] Palladium-catalyzed amidation of five-membered heterocyclic bromides that contain multiple heteroatoms was achieved for the first time using the Pd/ catalyst system. This system allows for efficient access to -arylated imidazoles, pyrazoles, thiazoles, pyrroles, and thiophenes in moderate to excellent yield. Experimental results and DFT calculations point to the need for electron-rich and especially sterically demanding biaryl phosphine ligand to promote these difficult cross-coupling reactions.
[图片：见正文]首次使用 Pd/催化剂体系实现了含多个杂原子的五元杂环溴化物的钯催化酰胺化。该体系可高效合成中等至优异产率的芳基取代咪唑、吡唑、噻唑、吡咯和噻吩。实验结果和 DFT 计算表明，需要富电子且空间位阻要求高的双芳基膦配体来促进这些困难的交叉偶联反应。
