申请人:American Cyanamid Company
公开号:US05194666A1
公开(公告)日:1993-03-16
An improved process for the synthesis of esters of 3,5,6-trichlorosalicylic acid in quantitative yield comprises reacting the acid with an alcohol under distillation conditions in the presence of a titanium ester or chelate catalyst, whereby byproduct ether formation from the alcohol is suppressed. The process is especially applicable to a process by which salicylic acid is chlorinated first in concentrated sulfuric acid and then with iodine catalyst to make the trichlorosalicylic acid which is extracted and then reacted with an alcohol and a titanium catalyst to make the ester.
一种改进的合成3,5,6-三氯水杨酸酯的工艺,在定量产率下,包括在蒸馏条件下,在钛酯或螯合催化剂的存在下,将水杨酸与醇反应,从而抑制醇生成的副产物醚。该工艺特别适用于一种工艺,即首先将水杨酸在浓硫酸中氯化,然后用碘催化剂使三氯水杨酸生成,然后提取并与醇和钛催化剂反应制备酯。