偶联反应 论文1(NJC).doc

Highly Efficient Palladium-Catalyzed Suzuki-Miyaura Cross-Coupling with Three-Dimensional Geometry α-Diimine Ligands under Mild Aerobic Conditions Ping Huo1, Wanyun Liu*1, Guangquan Mei*1 1Key Laboratory of Jiangxi University for Applied Chemistry and Chemical Biology, Yichun University, Yichun 336000, China The three-dimensional geometry 9, 10-dihydro-9, 10-ethanoanthracene-11,12-diimine /Pd(OAc)2 system has been developed for the catalytic cross-coupling of aryl halides with arylboronic acids. A combination of these α-diimines and Pd(OAc)2 was found to form a highly efficient catalyst for the Suzuki-Miyaura cross-coupling of various aryl bromides and activated aryl chlorides with arylboronic acids at room temperature in ethanol/aqueous media under ambient atmosphere, and excellent yields of products. The Suzuki-Miyaura cross-coupling reaction, involving the coupling of an arylboronic acid with an organohalide, has proven to be an extremely useful synthetic tool for the construction of biaryls1-8, which are present in a wide range of natural products, pharmaceuticals, agrochemicals, functional polymer materials and liquid crystals9-12. It is well-known that the Suzuki-Miyaura cross-coupling reaction can be efficiently carried out using phosphine ligands/palladium complex. Because of the superior donor capability and stabilization effects, the bulky and electron-rich phosphine ligands are outstanding in the palladium catalyzed Suzuki cross-coupling reaction13-18. However, serious drawbacks still exist in most phosphines, such as highly toxic and air- and moisture-sensitive19,20. These drawbacks severely hinder its usage. Therefore, in the past few years, great advances have been made in developing active and efficient catalysts by modifying traditional ligands and discovering phosphine-free ligands21-30. Recently, phosphine-free ligands with, such as heterocyclic carbenes31-36, β-ketoamine37-40, 2-aryl-2-oxazolines41 and other amines42-43, have also emerged for