Novel access to N,N'-diaryl-trans-1,2-diaminocyclohexane ligands. A cheap and easy way to prepare ligand for asymmetric transfer hydrogenation

International audience; N,N′-diaryl-trans-1,2-diaminocyclohexane ligands were prepared from 1,2-diaminocyclohexane and cyclohexanone derivatives via a heterogeneous palladium catalysis. In one step an alkylation followed by an aromatisation is performed under air or in the presence of an hydrogen trap. The interest of the synthesized ligands were evaluated in the reduction of aromatic ketones. The alcohols were efficiently and selectively obtained with an iridium complex and a mixture of formic acid and sodium formate.