申请人:DowElanco
公开号:US05480991A1
公开(公告)日:1996-01-02
5-Alkoxy[1,2,4]triazolo[1,5-c]pyrimidine-2 (3H)-thione compounds, such as 5-ethoxy-8-fluoro[1,2,4]triazolo[1,5-c]pyrimidine-2(3H)-thione, were prepared by treatment of a 5-alkoxy-1,2,4-triazolo-[4,3-c]pyrimidine-3(2H)-thione compound, such as 5-ethoxy-8-fluoro-1,2,4-triazolo[4,3-c]pyrimidine-3(2H)-thione, with an alkali metal alkoxide in an alcohol solvent selected so that the 5-alkoxy group, the alkoxide, and the alcohol all have the same alkyl group. The trialkylammonium salts of the 5-alkoxy-1,2,4-triazolo [4,3-c]pyrimidine-3(2H)-thione compounds were converted to 3-hydrocarbylthio-5-alkoxy-1,2,4-triazolo-[4,3-c]pyrimidine compounds by reaction with a hydrocarbyl halide, such as benzyl chloride. The products are useful intermediates in the preparation of 5-alkoxy[1,2,4]triazolo[1,5-c]pyrimidine-2-sulfonamide herbicides.
本文介绍了一种制备5-烷氧基[1,2,4]三唑并[1,5-c]嘧啶-2(3H)-硫脲化合物的方法,例如5-乙氧基-8-氟[1,2,4]三唑并[1,5-c]嘧啶-2(3H)-硫脲。该方法是将5-烷氧基-1,2,4-三唑并[4,3-c]嘧啶-3(2H)-硫脲化合物(例如5-乙氧基-8-氟-1,2,4-三唑并[4,3-c]嘧啶-3(2H)-硫脲)与碱金属烷氧化物在选择性溶剂(使5-烷氧基、烷氧化物和醇都具有相同的烷基)中反应制备而成。5-烷氧基-1,2,4-三唑并[4,3-c]嘧啶-3(2H)-硫脲化合物的三烷基铵盐可以通过与烃基卤化物(例如苄基氯化物)反应转化为3-羟基烷基硫代-5-烷氧基-1,2,4-三唑并[4,3-c]嘧啶化合物。该产品是制备5-烷氧基[1,2,4]三唑并[1,5-c]嘧啶-2-磺酰胺除草剂的有用中间体。