Investigation of the origin and synthetic application of the pseudodilution effect for Pd-catalyzed macrocyclisations in concentrated solutions with immobilized catalysts
作者:Elisabeth Brehm、Rolf Breinbauer
DOI:10.1039/c3ob41020j
日期:——
Immobilized Pd-complexes allowed macrocyclisations via the Tsuji-Trost-reaction in concentrated solutions. Systematic studies suggest that the origin of this pseudodilution effect is neither film diffusion nor gel diffusion, but the reduction in conformational freedom of intermediates and intramolecular prenucleophile activation. In contrast a pseudodilution effect could not be observed for Sonogashira-
固定的Pd复合物可以通过Tsuji-Trost反应在浓缩溶液中进行大环化。系统研究表明,这种假稀释作用的起源既不是膜扩散也不是凝胶扩散,而是中间体构象自由度的降低和分子内亲核试剂的活化。相反,对于Sonogashira-和Suzuki-大环化没有观察到假稀释作用。