The Research On Catalytic Synthesis Of Triazole-Like Containing-Nitrogrn Heterocyclic Compounds

1,2,3-triazoles is a kind of important functional compounds,which is widely used in the field of medicine and material Although it have extensive ues,it is not a natural product.The 1,3-dipolar cycloaddition of multikey intermediates and azid is the main synthetic methods.Heterogeneous catalysis has attracted much attention in the field of catalysis in recent years because of environment friendly,mild reaction conditions,simple operation and easy recycling of catalyst,and heterogenization of homogeneous catalysis has become a hot area.Under the background this paper studied the synthetic method of NH-1,2,3-triazoles that use the aromatic aldehyde,nitromethane and sodium azide as substrate and employ the acid-base bifunctional nanosphere as catalyst.The eeperimental results and conclusions summarized below:A magnetically separable core-shell-shell nano sphere,Fe3O4@nSiO2-SO3H@MS-NHCOCH3(n=nonporous,MS=microporous SiO2),was fabricated as an acid-base collaborative catalyst for the three-component cyclization of aromatic aldehydes,nitroalkane,and sodium azide to afford 1H-1,2,3-triazoles.The bifunctional heterogeneous catalyst showed high activity for this transformation and good chemoselectivity,and toxic HN3 was not released during the course of the reaction.A variety of aldehydes were transformed into the corresponding 5-aryl1H-1,2,3-triazoles in up to 98%yield.Furthermore,the catalyst could be recovered by using an external magnetic field and reused many times without any loss in activity.In contrast,a homogeneous catalyst system comprising ammonium acetate/acetic acid also worked in this three-component cyclization to afford 1H-1,2,3-triazoles.All triazoles were confirmed by 1H-NMR,13C-NMR and HPLC-MS,the melting point of all compounds were also determined.