Studies On The Rh-and Ru-catalyzed Conjugate Addition Reactions Of Arylboronic Acids To α,β-unsaturated Carbonyl Compoundsand Their Applications In Drug Synthesis

This dissertation focused on the study of rhodium-,ruthenium-catalyzed conjugate addition reactions of the arylboronic acidsand α, β-unsaturated carbonyl compounds. It covers:1. Rh(I)/Sunphos catalyst was applied to the rhodium-catalyzed conjugateaddition reactions between arylboronic acids and vinyl ketonesuccessfully. We optimized the reaction conditions and found that thesolvent was crucial for the conjugate addition, dioxane/H2O was the bestchoice and the water was necessary. Toterodine was synthesized withhigh ee value though conjugate addition reaction catalyzed by Rh (I)/Sunphos system.2. A simple and efficient ruthenium-catalyzed aryl boronic acid and vinylketone conjugate addition reaction was developed with RuCl2(p-cymene)]2as the catalyst. We found that this Ru-catalyzed systemfulfilled both the inhibition of the β-hydride elimination in the catalyticcycle, and minimized the protonolysis of arylboronic acids. Under thiscondition almost quantitative yield of the addition product was obtainedwith only1equivalent of boric acid. A number of aryl and alkenylboronic acids were tested and good to excellent yields were obtained. 3. Conjugate addition reaction of aryl boronic acid and an acrylic estercompound catalyzed by ruthenium was developed. By optimization ofreaction conditions, we found that the pH value of the reaction systemand the additives have a significant influence on the reaction results.Acidic conditions accelerated boric acid hydrolysis; alkaline conditionsfavor β-H elimination reactions. We found that the phenols are the bestadditives in our catalytic system. By using of2,6-di-tert-butylphenol asadditives, the β-hydride elimination products was reduced and theprotonylysis of the arylboronic acids was also suppressed.