Trisguanidinate Lanthanide Complexes: Syntheses, Structures, and Catalytic Activity for Mild Amidation of Aldehydes with Amines

A series of new trisguanidinate lanthanide complexes including the first THF-solvated trisguanidinate lanthanum complexes were synthesized and fully characterized. The complexes were found to be efficient catalysts for amidation of aldehydes with amines under mild conditions with a wide scope of substrates including pyrrolidine, piperidine, and morpholine, and one of the intermediates for this process, lanthanum amido complex {[(ⁱPrN)CNHⁱPr(NC₆H₄p-Cl)]₂La(NHC₆H₅)}₂·C₇H₈, was isolated.