Graphene-catalyzed Synthesis Of Bis(aminothiocarbonyl)disulfides

As a new carbon material, graphene (GP) is nontoxic and environmentally benign,showing diverse promising applications in catalysis. Bis(aminothiocarbonyl)disulfidesplay an important role in pharmaceutical chemistry, pesticide chemistry and rubbermanufacture. The traditional methods for synthesis of bis(aminothiocarbonyl)-disulfides are generally using large excess of unclean oxidants, producingunrecyclable wastes during the redox process and causing environmental pollution.Therefore, more efficient and environmentally benign method for synthesis ofbis(aminothiocarbonyl)disulfides is still of great necessity.In this thesis, reduced graphene oxide (rGO) was first used in aerobic oxidativecoupling of dithiocarbamates which generated in situ from secondary amines and CS2,which provided an efficient access to the one-pot synthesis of bis(aminothiocarbonyl)-disulfides. We prepared graphite oxide (GO) through Hummers method, then obtainedfour types of rGO by using different reducing agents and screened in the reaction. TherGO reduced by hydrazine hydrate was found superior to the others. Thecharacterization of rGO reduced by hydrazine hydrate was performed using FT-IR,X-ray diffraction, transmission electron microscopy, thermogravimetric analysis. Thestructures of all the products were indentified by1H NMR and13C NMR, and thenovel spiro compound was also characterized by high resolution mass spectrometryand X-ray single crystal diffraction.The advantages of this method include easy operation, simple isolation of theproduct, and utility of environmentally benign oxidant and catalyst. Moreover, rGOcould be reused at least four times without any loss of catalytic activity.