bis‐(Aminophenyl)ferrocene ligand for palladium free CuI catalyzed Csp²−Csp cross‐coupling reaction

Abstract

Two new ferrocene based molecules S,S′‐bis(4‐aminophenyl)ferrocene‐1,1'‐bis(carbothioate) (I) and S,S′‐bis(3‐aminophenyl)ferrocene‐1,1'‐bis(carbothioate) (II) have been synthesized via a thioester linkage. The prepared compounds have been successfully applied as ligands for the CuI catalyzed Sonogashira coupling reaction. The ligands are highly effective for the Csp2−Csp coupling between alkyne and iodobenzene and bromobenzene. Corresponding 1,2‐disubstituted alkynes could be synthesized from both aryl and alkyl alkynes in high yield by using catalytic amount of CuI in presence of bis(3‐aminophenyl)ferrocene derivative in dioxane at 50 °C.