摘要
磺酰脲类除草剂是一类高效的除草剂,被广泛应用在园林、旱地、防虫水田、森林防火隔离带和非耕地杂草等各个方面。2-氨基-4,6-二甲氧基嘧啶是磺酰脲类除草剂合成的重要中间体,本选题主要采用以硝酸胍和丙二酸二乙酯为起始原料,经过环合生成2-氨基-4,6-二羟基嘧啶,再通过与三氯氧磷反应,三乙胺做催化剂的条件下氯化得到2-氨基-4,6-二氯嘧啶,最后与甲醇钠反应,甲氧基化得到目标化合物2-氨基-4,6-二甲氧基嘧啶。试验通过探讨实验条件对产率的影响,优选最佳反应条件,总收率达到53.3%。
Sulfonylurea herbicides are a class of highly effective herbicides,widely used in gardens, dry land, paddy pest control, forest fire buffer zone and non-arable weeds and other aspects.2-amino-4,6-dimethoxypyrimidine is an important intermediate for the synthesis of sulfonylurea herbicides,the topics mainly guanidine nitrate and diethyl malonate as starting material, through cyclization of 2-amino-4,6-dihy- droxypyrimidine, and then the reaction with phosphorus oxychloride, triethylamine as catalyst chlorination conditions to give 2-amino- 4,6-dichloropyrimidine, and the final sodium methanolate, methoxylation to obtain the target compound 2-amino-4,6-dimethoxypyrimidine. Test experimental conditions by exploring the impact on the yield, preferably optimal reaction conditions, the total yield of 53.3%.
