Copper-Catalyzed MultiComponent Reactions

Copper-catalyzed azide-alkyne cycloaddition (CuAAC) reactions recently have attracted much attention in organic methodology field. More and more chemists are interested in tandem/cascade multicomponent reactions based on CuAAC process. Multicomponent reactions (MCRs) via CuAAC process are reviewed in this dissertation. Our research focus on the multicomponent reactions of azide, alkyne and Baylis-Hillman adducts, which can form numerous of heterocycles and other crucial compounds. The results and details are shown below:1. An efficient one-pot method was used to prepare a series of 1,4-disubstituted-1,2,3-triazoles and double triazoles in water from a variety of Baylis-Hillman adducts, sodium azide and terminal alkynes using Cu (I) as catalyst. This method was simple, efficient and base free. In addition, we proposed possible mechanism about forming double triazoles.2.4-(Alkoxycarbonyl)-pent-4-enimidates were regioselectively synthesized via a copper-catalyzed four-component reaction of Baylis-Hillman adducts with terminal alkynes, sulfonyl azides and alcohols. The procedure was concise, general and efficient (42%-81%). This method bridged the gap between ketenimine chemistry and Baylis-Hillman chemistry. It was noteworthy that a 3-CR product was isolated instead of formation of the predicted 4-CR adduct when a secondary alcohol, aliphatic alkyne or aliphatic sulfonyl azide was used as the substrate. In these cases, the Baylis-Hillman adducts failed to participate in this cascade process. The resulting pentenimidates could be further transformed to indene.