申请人:Ciba-Geigy Corporation
公开号:US04507146A1
公开(公告)日:1985-03-26
2,4-Diamino-6-halo-5-trifluoromethylpyrimidines of the formula ##STR1## wherein X is a halogen atom, especially chlorine or fluorine, and R.sub.1 and R.sub.2 independently of one another are each hydrogen, C.sub.1 -C.sub.6 -alkyl or C.sub.3 -C.sub.6 -cycloalkyl, or together form a C.sub.3 -C.sub.7 -alkylene bridge, have outstanding selective-herbicidal properties, and are suitable for controlling weeds in crops of cultivated plants, such as maize, cereal or soya-bean. They are produced by aminating 2,4,6-trihalo-5-trifluoromethylpyrimidine, which for its part is obtainable by fluorination of 2,4,6-trihalopyrimidine-5-carboxylic acid. The 2,4,6-trihalo-5-carboxylic acids are novel intermediates, and are obtained by oxidizing 2,4,6-trihalo-2-methyl-, -halomethyl- or -formyl-pyrimidine in sulfuric acid by means of chromium trioxide.
2,4-二氨基-6-卤代-5-三氟甲基嘧啶的化学式为##STR1## 其中X是卤素原子,特别是氯或氟,R.sub.1和R.sub.2彼此独立地为氢、C.sub.1-C.sub.6-烷基或C.sub.3-C.sub.6-环烷基,或者一起形成一个C.sub.3-C.sub.7-烷基桥,具有出色的选择性除草性能,并适用于控制玉米、谷物或大豆等栽培植物作物中的杂草。它们通过对2,4,6-三卤代-5-三氟甲基嘧啶进行氨基化而制备,而后者可通过对2,4,6-三卤代嘧啶-5-羧酸进行氟化而获得。2,4,6-三卤代-5-羧酸是新颖的中间体,通过在硫酸中用三氧化铬氧化2,4,6-三卤代-2-甲基、-卤代甲基或-甲酰基嘧啶而获得。