Sandmeyer-Type Reductive Disulfuration Of Anilines

Unsymmetric disulfides play an important role in the fields of medicinal chemistry,food chemistry and natural products.Disulfide bonds can enhance the activity of drugs and stabilize the structure of proteins,which is extremely important for the protein to perform its function.In recent years,although significant progress has been made toward synthesis of unsymmetric disulfides using novel disulfide reagents,these approaches are often limited to a certain extent by following points: starting materials are not easily available;homocoupling is unavoidable;requiring a transition metal catalyst and ligand.Therefore,it is particularly important to develop an universal,green,mild and efficient method for the preparation of unsymmetric disulfides.In this thesis,the synthetic methods of unsymmetric disulfides and the research progress of the Sandmeyer reactions were initially summarized.On this basis,a transition metal/ligand-free disulfuration of anilines with disulfur transfer reagents has been also realized.The reactions were obtained in good yields,broad substrate scope,and can be scaled up to gram scale.This article consists of the following three parts:1.Application of unsymmetric disulfide compound in medicine,organism,organic synthesis and material and preparation method were described in this part in detail.2.The development process of Sandmeyer reaction was introduced.On this basis,the strategy of preparing unsymmetric disulfide compounds by constructing C-SSR bonds with aniline compounds and disulfide reagents was developed.By screening of solvent,anilines,reducing agents,disulfide reagents,diazotization reagents and the temperature,the optimal reaction conditions were determined,and then the universality of the reaction was investigated.Finally,The mechanism has been initially studied.3.Unsymmetric aromatic disulfides,heterocyclic aromatic disulfides,and complex aromatic disulfides were synthesized.Their structures were determined by Nuclear Magnetic Resonance Spectroscopy,Infrared Spectroscopy and High-Resolution Mass Spectrometry.