The invention provides a process for the preparation of a carboxylic acid of formula (IV) (which is useful as a safener for herbicides): wherein R
1
is hydrogen or chlorine, comprising the steps of: (i) subjecting a compound of formula (V) wherein: R
1
is as defmed above; and R
2
is C
1
-C
18
alkyl; C
1
-C
6
alkoxyC
1
-C
8
alkyl-; optionally substituted phenyl; or optionally substituted benzyl; to hydrolysis under acidic conditions to give a solution of a quinolinium salt; and (ii) addingbase to the solution obtained in step (i) to give the free carboxylic acid (IV). The invention also provides a solid (e.g. particulate) form of one quinoline carboxylic acid compound within formula (IV) defmed by R
1
being chlorine;and novel intermediates useable in the above process.
该发明提供了一种制备
化学式(IV)的
羧酸的方法(作为
除草剂的安全剂):其中R1是氢或
氯,包括以下步骤:(i)将化合物
化学式(V)置于酸性条件下
水解,其中:R1如上定义;R2为C1-C18烷基;C1-C6烷氧基C1-C8烷基;可选择取代的苯基;或可选择取代的苄基;以得到
喹啉盐的溶液;和(ii)向步骤(i)中获得的溶液中加入碱以得到自由的
羧酸(IV)。该发明还提供了一种固体(例如颗粒)形式的
喹啉羧酸化合物,其由R1为
氯定义;以及上述过程中可用的新颖中间体。