A direct protocol for Rh-catalyzed C-H amidation of ferrocenes in a ball mill using dioxazolones as the amide source under solvent-free conditions was developed. The corresponding ortho-aminated products were formed in 3 hours and the yields were up to 99% in the absence of base. This method could be a typically sustainable and environmental-friendly alternative method to traditional methodologies, with the advantages of wide substrate range, good functional group tolerance and gram-scale synthesis.
A KOH-promoted cascade C-Cl bond activation and amidation of trichloromethyl aromatic compounds with formamides using water as a solvent has been developed. This methodology suggested an alternative synthetic approach for the synthesis of aryl amide compounds in the absence of catalysts, additives and organic solvents. In addition, the yields of gram-scale reactions are good and provide a basis for synthetic application.
We developed a Cp*Rh(III)-catalyzed C-H arylation of ferrocenethionamides with arylboronic acids for the synthesis of aryl-ferrocenes under mild and base-free conditions, using Ag2 CO3 as oxidant. The reaction results in high yields and excellent regioselectivity accommodating a broad scope of substrate range and functional group compatibility, and provides an alternative protocol for the generation of highly functionalized aryl-ferrocene compounds.
The first Ir(I)-catalyzed thioamide-assisted C-H arylation of ferrocenes with aryl boronic acids under base-free mild reaction conditions in the presence of Ag2CO3 as an oxidant with eco-friendly 2-MeTHF as a solvent was developed. This reaction has a wide range of substrates (37 examples) and functional group tolerance (18-94% yields), and provides promising access to aryl thioamide-ferrocene compounds with good yields and regioselectivity.