Synthesis of Two Types of 1,3‐Diarylpropane Derivatives by Cobalt‐Catalyzed Cycloaddition of 1,6‐Diynes

Abstract

The development of the synthesis of 1,3‐diarylpropanes is important because some of them have been reported to have biological activities. We report herein the synthesis of two types of 1,3‐diarylpropane derivatives by using cobalt‐catalyzed cycloaddition of 1,6‐diynes. CoCl(PPh₃)₃‐catalyzed cyclotrimerization of 1,6‐diynes afforded a series of 1,3‐diarylpropane derivatives. Furthermore, double [4+2]‐cycloaddition between 1,6‐diynes and 1,3‐dienes proceeded in the presence of CoBr₂−DPPE−Zn−ZnBr₂, and the successive oxidation by 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ) afforded another type of 1,3‐diarylpropane derivatives.