2010年诺贝尔化学奖获得者及其主要贡献

2010年诺贝尔化学奖获得者及其主要贡献

美国化学家RichardF.Heck 日本科学家根岸荣一和铃木章

贡献

①Heck Reaction

The palladium-catalyzed C-C coupling between aryl halides or vinyl halides and activated alkenes in the presence of a base is referred as the "Heck Reaction". Recent developments in the catalysts and reaction conditions have resulted in a much broader range of donors and acceptors being amenable to the Heck Reaction.

One of the benefits of the Heck Reaction is its outstanding trans selectivity.

机理

最近文献

An Efficient and General Method for the Heck and Buchwald-Hartwig Coupling Reactions of Aryl Chlorides

D.-H. Lee, A. Taher, S. Hossain, M.-J. Jin, Org. Lett., 2011, 13, 5540-5543.

Palladium-Catalyzed Heck Reaction of Aryl Chlorides under Mild Conditions Promoted by

Organic Ionic Bases

H.-J. Xu, Y.-Q. Zhao, X.-F. Zhou, J. Org. Chem., 2011, 76, 8036-8041.

Efficient Aqueous-Phase Heck Reaction Catalyzed by a Robust Hydrophilic Pyridine-Bridged Bisbenzimidazolylidene-Palladium Pincer Complex

Z. Wang, X. Feng, W. Fang, T. Tu, Synlett, 2011, 951-954.

An efficient and simple protocol for phosphine-free Heck reactions in water in the presence of a Pd(L-proline)2 complex as the catalyst under controlled microwave irradiation conditions is versatile and provides excellent yields of products in short reaction times. The reaction system minimizes costs, operational hazards and environmental pollution.

B. K. Allam, K. N. Singh, Synthesis, 2011, 1125-1131.

②Suzuki Coupling

The scheme above shows the first published Suzuki Coupling, which is the

palladium-catalysed cross coupling between organoboronic acid and halides. Recent catalyst and methods developments have broadened the possible applications enormously, so that the scope of the reaction partners is not restricted to aryls, but includes alkyls, alkenyls and alkynyls. Potassium trifluoroborates and organoboranes or boronate esters may be used in place of boronic acids. Some pseudohalides (for example triflates) may also be used as coupling partners.

机理

One difference between the Suzuki mechanism and that of the Stille Coupling is that the boronic acid must be activated, for example with base. This activation of the boron atom enhances the polarisation of the organic ligand, and facilitates transmetallation. If starting materials are substituted with base labile groups (for example esters), powdered KF effects this activation while leaving base labile groups unaffected.

In part due to the stability, ease of preparation and low toxicity of the boronic acid compounds, there is currently widespread interest in applications of the Suzuki Coupling, with new developments and refinements being reported constantly.

最近文献

Stereoconvergent Amine-Directed Alkyl-Alkyl Suzuki Reactions of Unactivated Secondary Alkyl Chlorides

Z. Lu, A. Wilsily, G. C. Fu, J. Am. Chem. Soc., 2011, 133, 8154-8157