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Aminopyridine is a class of amino-containing heterocyclic compounds, which are widely used as an important intermediate , pesticides, pharmaceuticals, energetic materials and other industries . With this class of compounds widely used in various fields , the synthesis of these compounds has become the focus of research and development of fine chemical intermediates in the preparation of industry and new outsourcing services industry . 3,5 - diaminopyridine as high energy insensitive explosives 2,4,6 - trinitro- 3,5 - diaminopyridine synthesis of important intermediates, has broad application prospects in the field of energetic materials . The existing two synthetic methods , however , is facing serious pollution and complicated to operate under harsh conditions , extremely difficult to obtain raw materials , catalysts are expensive and many other issues , a serious impediment to a wide range of applications of 3,5 - diamino pyridine and its derivatives . 3,5 - dimethyl pyridine as raw materials, through the oxide , ammonia solution , Hofmann rearrangement of some of the more simple and efficient reaction design and synthesis of 3,5 - diamino pyridine and its derivatives more value synthetic route , through the optimization and the optimum reaction conditions . Experimental results show that the route practicable , the total yield amounted to 79.4% ( pyridine-3 ,5 - carbamate total ) , 75.4% ( 3,5 - 2 - acetylamino- pyridin- meter ) , purity more than 99%. The product of the use of modern analytical instruments red at the spectrum , 1H NMR , mass spectrometry , elemental analysis for structural characterization confirmed its structure .
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