A series of dendritic ligands with a 2,2'-bipyridine core was synthesized through the coupling of 4,4'-dihydroxy-2,2'-bipyridine with poly(arylether) dendron in fair yields. The corresponding copper(II) trifluoromethanesulfonate (triflate) dendrimers were applied as a Lewis acid catalyst to the Diels-Alder reaction. A positive dendritic effect on the chemical yields of adducts was observed. (c) 2006 Elsevier Ltd. All rights reserved.
Synthesis of Novel Dendritic 2,2‘-Bipyridine Ligands and Their Application to Lewis Acid-Catalyzed Diels−Alder and Three-Component Condensation Reactions
作者:Takahito Muraki、Ken-ichi Fujita、Masato Kujime
DOI:10.1021/jo070767a
日期:2007.10.1
dendritic Cu(OTf)2 catalysts were used for Diels−Alder and three-component condensationreactions. The dendritic Cu(OTf)2-catalyzed Diels−Alder reaction proceeded smoothly, and these dendritic catalysts could be recycled without deactivation by reprecipitation. Three-component condensationreactions such as Mannich-type reactions also proceeded not only in dichloromethane but also in water. Furthermore