Synthesis Of3-amino-2,4,6-trinitrostilbenes

3-Amino-2,4,6-trinitrotoluene was effectively synthesized with3-methylaniline as starting material via protection of amino group, nitration and hydrolyzation processes. The precursor condensed with aromatic aldehydes through Knoevenagel reaction to form various3-amino-2,4,6-trinitrostilbenes, which could be used as intermediates in the preparation of heat-resistant and non-linear optical materials.N-(3-methylphenyl)carbamate derived from3-methylaniline and ethyl chlorocarbonate over triethylamine acid acceptor was nitrated with nitric and sulfuric acids under mild conditions to afford N-(3-methyl-2,4,6-trinitrophenyl)carbamate. Followed by hydrolyzing the nitration product in the presence of hydrochloric acid,3-amino-2,4,6-trinitrotoluene was achieved in a total yield of79.0%.An efficient one-pot procedure for the preparation of3-amino-2,4,6-trinitrotoluene from N-(3-methylphenyl)carbamate was also described. A high yield of88.2%was obtained using mixed acid as nitrating reagent in n-propyl alcohol/water media. The processes avoided a redundant separation process and purification of N-(3-methyl-2,4,6-trinitrophenyl)carbamate.Microwave-assisted methodology was employed to promote the synthesis of3-amino-2,4,6-trinitrostilbenes under solvent-free systems. Silica-gel was introduced to support the reactants to form various polynitro compounds, such as3-amino-4’-methyl-2,4,6-trinitrostilbene,3-amino-4’-chloro-2,4,6-trinitrostilbene,3-amino-2’,4’-dichloro-2,4,6-trinitrostilbene,3-amino-4’-nitro-2,4,6-trinitrostilbene,3-amino-4’-bromo-2,4,6-trinitrostilbene, and3-amino-2’-chloro-2,4,6-trinitrostilbene. The compounds synthesized were characterized by1HNMR, FT-IR and MS analyses.