| Salen-type complex and quaternary halide or organic bases were used as the binary catalyst in the cycloadditon of carbon disulfide and epoxide, carbon disulfide and episulfide, carbon dioxide and aziridines, respectively.A series of alkyl, halogen substituted Schiff base ligands were prepared. SalenAlEt, fromed by the reaction of H2Salen and Et3Al, was employed in the cycloadditon of carbon disulfide and epoxide (or episulfide). SalenCo(II) complexes derived from the reaction of H2Salen ligand and Co(OAc)2, were oxided to afford the SalenCo(III) complexes in the presence of acid under an atmosphere of oxygen. It was used in the cycloaddition of aziridines and carbon dioxide in situ. -Propylene oxide was used as the starting material for the preparation of episulfide. Also, propylene oxide was ring-opened after the reaction of ammonium or amine to afford the p-amino alcohol. Then the p-amino alcohol was transformed into the corresponding aziridine through Wenker method.All the catalysts and the products of the catalytic reaction were characterized by 1H NMR and FT IR. The purities of the aziridines were tested by Gas Chromatography and their structures were determined by 1H NMR.This electrophile-nucleophile catalytic system (SalenAlEt/quaternary ammonia salt) was effective for the coupling reaction of carbon disulfide and epoxide under mild conditions. A series of factors such as the amount of catalyst, the ratio of the substrates, temperature, time etc were investigated. The optimized condition was determined: 100℃, PO/CS2/Cat.=1000/200/1, 9hrs, with a yield of 94%. The major product and its ratio could be varied according to different conditions employed.In the coupling reaction of aziridine and carbon dioxide which was catalyzed by SalenCo(III)/quaternary system, two regioselective products were obtained. Compound 3, 4-dimethyloxazolidin-2-one was reported the first time and its structure was determined by 1H NMR when 1, 2-dimethylaziridine was used as substrate.
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