An efficient iron porphyrin Lewis acid-catalyzed cycloaddition of aziridines with aldehydes has been developed to provide oxazolidines with high regio- and diastereoselectivity. The cycloaddition proceeds in toluene with 1 mol % of the iron catalyst at 25 °C. A theoretical study and synchrotron-based X-ray absorption fine structure measurements provided fundamental insights into the aziridine–iron porphyrin complex, which is the key intermediate for the generation of the 1,3-dipole synthon.

Alcohols react with arenes in the presence of cationic iron(III) porphyrin catalyst. The reaction involves the formation of the C-C bond via dehydration, which is formal Lewis acid catalyzed Friedel-Crafts reaction.

The enantioselective oxa-Diels–Alder reaction of nonactivated substrates by utilizing FeCl3 and a 1,1′-bi-2-naphthol (BINOL) derived chiral phosphoric acid as a multiple activation catalyst is reported. Various oxygen-containing six-membered heterocycles were obtained in high yields and in an enantioselective manner. Density functional theory (DFT) calculations elucidate that both Lewis acidic and Brønsted acidic moieties in the catalyst system synergistically activate two lone pairs of an aldehyde to facilitate enantioselective addition reaction of dienes.

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The effects of preparation variables (temp., aging time, drying temp. and time) on chemical composition and reducibility of precipitated precursors of Ni ‐ SiO2 catalysts are studied using TGA.