Synthesis of nitro aromatic compounds using ionic liquids as catalysts or green solvents is a hot spot in the study of nitration. A series of Br(?)nsted acidic ionic liquids were synthesized and characterized by 1H NMR and IR, and used in the nitro lysis of hexamethylenetetramine and nitration of toluene.The experimental study was carried out on the direct nitrolysis of hexamethylenetetramine to synthesize hexahydro-1, 3, 5-trinitro 1,3, 5-triazine (RDX) with nitric acid (95%) in the presence of Br(?)nsted acidic ionic liquids. Various ionic liquids, and various parameters, such as the equivalents of ionic liquid, mass ratio of nitric acid (95%) to the starting material and reaction time were investigated. Catalyzed by ionic liquids [Hmim]NO3, the yield of RDX was 75.9% under the optimum reactive conditions, and improved by 7.6% compared to the system without ionic liquid.The Br(?)nsted acidic ionic liquids based on N,N,N-Triethyl ammonium such as: (Et3NH)xH3-xPMo12O40, [SO3H(CH2)4NEt3]xH3-xPMo12O40 (x=1, 2, 3), [HSO3(CH2)4NEt3]X (X-= NO3-, pTSO-) were synthesized and used in the nitration of toluene as acidic catalysts. The effects of various parameters on the yields of mono-nitrotoluene and regionselectivities for nitration of toluene, such as amount of nitric acid (67%), amount of ionic liquid, reaction time and temperature were investigated. Catalyzed by [SO3H(CH2)4NEt3]H2PMo12O40 the yield of mono-nitrotoluene was 50.7%, and the ratio of o-nitro- to para-isomers was 1.32.
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