Efficient One-Pot Synthesis of Multi-Substituted Dihydrofurans by Ruthenium(II)-Catalyzed [3+2] Cycloaddition of Cyclic or Acyclic Diazodicarbonyl Compounds with Olefins
作者:Likai Xia、Yong Rok Lee
DOI:10.1002/adsc.201300245
日期:2013.8.12
AbstractRuthenium(II)‐phosphine complexes‐catalyzed [3+2] cycloadditions were conducted to synthesize a variety of dihydrofurans by reactions of cyclic or acyclic diazodicarbonyl compounds with olefins. This method represents a direct and efficient one‐pot synthesis for multi‐substituted dihydrofurans under mild reaction conditions with an excellent regioselectivity. Furthermore, to reduce reaction times and increase yields of dihydrofurans, microwave‐assisted tris(triphenylphosphine)ruthenium(II) chloride/ 1‐butyl‐3‐methylimidazolium tetrafluoroborate Ru(PPh3)3Cl2/[Bmim]BF4}‐catalyzed reactions were also developed. The synthesized dihydrofurans can be readily converted into biologically interesting tetrahydroindoles.magnified image
AgBF<sub>4</sub>/[Bmim]BF<sub>4</sub>-Catalyzed [3+2] Cycloaddition of Cyclic Diazodicarbonyl Compounds: Efficient Synthesis of 2,3-Dihydrofurans and Conversion to 3-Acylfurans
A novel and efficient method for the synthesis of 2,3-dihydrofurans bearing a variety of substituents on the dihydrofuran ring was achieved by the reaction of cyclicdiazodicarbonylcompounds with styrene and vinyl acetate. The key strategy was AgBF/[Bmim]BF-catalyzed [3+2] cycloaddition. The synthesized dihydrofurans with an acetate group were further converted to the corresponding 3-acylfurans.