申请人:IMPERIAL CHEMICAL INDUSTRIES PLC
公开号:EP0121320A1
公开(公告)日:1984-10-10
A 2-oxo-5-methyl-5, 6-dihalopiperidine is contacted in a high boiling solvent, preferably trichlorobenzene, with a stoichiometric excess, up to 70 mole % excess, of a chlorinating agent, preferably phosphorus oxychloride or phosgene, at an elevated temperature between 80 and 130°C. The solution of 2-chloro-5-methylpyridine so obtained may be used directly for further chlorination to form 2-chloro-5-trichloromethylpyridine with, for example, chlorine gas in the presence of a free radical initiator. This chemical intermediate is useful in the synthesis of certain herbicidal compounds.
将 2-氧代-5-甲基-5, 6-二卤代哌啶在高沸点溶剂(最好是三氯苯)中,与按比例过量(最多为 70 摩尔%过量)的氯化剂(最好是氧氯化磷或光气)在 80 至 130°C 的高温下接触。这样得到的 2-氯-5-甲基吡啶溶液可直接用于进一步氯化,例如在有自由基引发剂存在的情况下,用氯气形成 2-氯-5-三氯甲基吡啶。这种化学中间体可用于合成某些除草化合物。