3,7,9,11-Tetraoxo-2,4,6,8,10-pentaaza [3.3.3] Propellane:Improvement On Synthesis,Derivatives And Properties

Heterocyclic propellanes containing nitrogen is a kind of important organic compound,which has important applications in the synthesis of natural products,biological active small molecules and high energy density materials.In this kind of material,the researches on synthesis and properties of 3,7,9,11-tetraoxo-2,4,6,8,10-penta-aza[3.3.3]propellanes are very limited.In this paper,the modified synthesis of glycoluril derivatives and mono-substituted3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza-[3.3.3]propellanesunder microwave radiation was studied.A series of multi-substituted 3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza[3.3.3]propellanes were obtained by using K₂CO₃ as catalyst.At last,we studied the nitration,solubility and thermodynamics behavior of 3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza[3.3.3]propellane derivatives.The specific contents are as follows.Firstly,the improved preparation of 3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza[3.3.3]-propellane skeleton and its mono-substituted derivatives.Based on diethyl tartrate as raw material,microwave-assisted synthesis of a series of N,N'-disubstituted glycoluril dimethylformamide derivatives was provided,then a series of mono-substituted 3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza[3.3.3]propellanes were obtained in the catalyst of p-toluene sulfonic acid under microwave heating mode.The use of microwave irradiation in the optimization process shortens reaction times largely without reducing yields.Due to the the inconvenient use of NaH,a series of multi-substituted3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza[3.3.3]propellanes were obtained by using K₂CO₃ in replace of NaH as catalyst,I₂ as accelerator and DMF as solvent.The optimization of all the reaction conditions including reaction time,reaction temperature and solvent were done.Secondly,the nitrations of 3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza[3.3.3]propellane derivatives.Taking into account the basic skeleton of 3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza[3.3.3]-propellane is highly similar to that of glycoluril,and glycoluril nitro derivatives are one kind of high energetic density compounds.Therefore,the designs and nitrations of3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza[3.3.3]propellanes and theirs derivatives were studied.When 3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza[3.3.3]propellane was nitrated with trifluoro-acetic anhydride and fuming nitric acid,2,6,10-trinitro-3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza[3.3.3]propellane was obtained;but 2,6-dinitro-3,7,9,11-tetraoxo-2,4,6,8,10-penta-aza[3.3.3]propellane was gotten by using H₂SO₄/HNO₃ or NO₂BF₄ as nitration reagents.2,6-Dinitro-3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza[3.3.3]propellane was further successfully nitrated with trifluoroacetic anhydride and fuming nitric acid to give two dinitro-substituted glycoluril derivatives and their structures were confirmed by X-ray crystallographic determine.10-?4-NO₂-Bn?-3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza[3.3.3]-propellane was obtained by the nitrification of 10-Bn-3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza[3.3.3]-propellane with concentrated nitric acid,and the mixture of trinitro-and tetranitro-substituted propellanes was obtained when TFAA/HNO₃ or Ac₂O/HNO₃ as nitration reagents.The other two dinitro-substituted glycoluril diethyl esters were gotten when another route for the synthesis of nitro-substituted 3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza-[3.3.3]propellanes based on nitro glycoluril derivatives as raw materials was choiced.In this processes,the effects of reaction time,reaction temperature and nitrating agent dosages were studied.Thirdly,Determination of the solubility of 3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza[3.3.3]propellane and thermodynamics performance of its derivatives.There is not any report about the solubility and thermodynamics performance of3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza[3.3.3]propellane in the literature.The solubility of3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza[3.3.3]propellane was measured in pure water and other eleven organic solvents including methanol,acetonitrile,acetone,ethyl acetate,ethanol,tetrahydrofuran,n-propanol,i-propanol,dioxane,ethylene glycol and toluene in the temperature range from 273.15 K to 318.15 K under a pressure of 0.1 MPa,respectively,and the measurements were performed by the equilibrium method with ultraviolet detection,the results showed that the solubility increases linear with growth of temperature in observed solvents.All the deterimented soluilities in all mentioned solvents were correlated with temperature by using the ideal solution model,Apelblat model,Yaws model,?h equation and NRTL model.Furthermore,the?_solH,?_solS and?_solG in twelve solvents was calculated.The thermodynamics properties of some 3,7,9,11-tetraoxo-2,4,6,8,10-pentaaza[3.3.3]propellane derivatives were studied,and Kissinger equation and Ozawa equation were used to calculate the correlation of activation energy,activation enthalpy and activation Gibbs free energy.Finally,the characterizations of all products and confirmation of some structures by X-ray measurement.The structures of all products were confirmed by IR,NMR and mass spectrum,and the structures of some products were confirmed by X-ray crystallographic determination.