Metal-Free Mediated Decomposition Of N-tosylhydrazones And Synthesis Of Trizole Derivatives

Transition-metal-catalysis has been well applied for the construction of carbon-carbon and carbon-heteroatom during the explosion of modern organic chemistry. Despite the advances of transition-metal-catalyzed approaches, these reactions are restricted due to the toxicity, high cost of transition metals and harsh reaction conditions. This research has developed methods for green, mild and efficient process based on transition-metal free, and mainly consists of the following contents:N-tosylhydrazones have been attracted great interest because it can be readily prepared and can be used for the generation of diazo compounds. At first, according to the published results of N-tosylhydrazones, our group's objectives are based on the N-tosylhydrazones as the starting substrates, developing a decomposition of N-tosylhydrazones promoted by (NH4)2S2O8 and Cs2CO3, when (NH4)2S2O8(1.0 eq), Cs2CO3(1.0 eq), acetomitrile,100? and 6h was conducted as the optimum reaction conditions, a series of hydrazines were abtained. We have developed a noval metal-free sequential construction of C-N couplings, distinguished by lack of any expensive transition metals, operational simplicity and reaction time.Secondly, a highly efficient synthesis of E-vinyl sulfones was emerged by using Iodobenzene diacetate triggerring decomposition of N-tosylhydrazones. For the system PIDA (1.1 eq) and K2CO3(1.0 eq), the substrates translated into E-vinyl sulfones yield 68.2?84.7% in the condition of N,N-Dimethylformamide,80? and 4h. The system of transition-metal free was adapted for selective synthesis method of C-S bond formation and sulfones. The advantages of the synthesis are the availability of starting materials, easy to operation and low energy, it comforms to the trend and requirement of green organic chemistry.Thirdly, functional group can be decorated in the upper and lower edge of calixarene by a series of reactions. The functionalized calixarenes have potent prospects in molecular recognition, simulation enzyme, biomedical and phase transfer catalyst. And compounds containing three triazole groups have tremendous value in biology and pharmacy, such as anti-virus, anti-seizure, anti-bacterial, anti-allergy. Synthesis of 1,2,3-triazoles derivatives must be catalyzed by Cu and used azide-alkyne as substrates in the 1,3-dipolar cycloaddition reactions. In this study, we used the structure of calixarene as the basic framework to construct noval calix[4]arene derivatives bearing 1,2,3-triazole moiety at the lower rim under metal-free simple synthetic procedures using anhydrous potassium carbonate as catalyst in good yield. The structures of these compounds were confirmed by means of 1H NMR,13C NMR, ESI-MS and single-crystal X-ray diffraction. The preliminarily functional studies for these compounds such as thermal analysis and fluorescent spectra have been discussed.