Study On Nitration Of Hexamethylenetetramine And Toluene In Presence Of Br(?)nsted Acidic Ionic Liquids

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)_xH_3-xPMo₁₂O₄₀, [SO₃H(CH₂)₄NEt₃]_xH_3-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]H₂PMo_12O40 the yield of mono-nitrotoluene was 50.7%, and the ratio of o-nitro- to para-isomers was 1.32.