Aromatic donor–acceptor interaction as the driving force to assemble cooperative catalysts is described. Pyrene/naphthalenediimide functionalized Co­(III)-salen complexes self-assembled into bimetallic catalysts through aromatic donor–acceptor interactions and showed high catalytic activity and selectivity in the asymmetric ring opening of various epoxides. Control experiments, nuclear magnetic resonance (NMR) spectroscopy titrations, mass spectrometry measurement, and X-ray crystal structure analysis confirmed that the catalysts assembled based on the aromatic donor–acceptor interaction, which can be a valuable noncovalent interaction in supramolecular catalyst development.

The development of several in situ generated catalyst systems for Ti-catalyzed oxidative nitrene transfer reactions is reported. The simplest and widely applicable catalyst system, TiCl 4 (THF) 2 / Zn 0 , can be set up on the benchtop under air. This system uses commercially available reagents and can be used as an entry point for Ti II /Ti IV multicomponent redox reactions for the synthesis of pyrroles, α,γ-unsaturated imines, α,β-unsaturated imines, cyclopropylimines, and arenes.

A series of ferrocenium (Fc, FcCO2H, FcCO2Me, and Fc­(Me)10) and cobaltocenium (Cc, CcCO2H, CcCO2Me) salts were prepared and explored as air- and water-tolerant homogeneous catalysts. They were found to be active catalysts at room temperature for the Friedel–Crafts alkylation of trans-β-nitrostyrene and N-methylindole and the Diels–Alder cycloaddition of 1,3-cyclohexadiene with methyl vinyl ketone. These catalysts are valuable additions to more traditional Lewis acids in that they are soluble in nonpolar media, did not decompose the starting materials, and dual activation exploiting both the Lewis (metal) and Brønsted acid (CO2H) centers was observed.

The catalyst activity of bis-acceptor functionalized Co(iii)–salen in hydrolytic kinetic resolution can be fine-tuned by introducing a proper donor compound.