Disclosed is a process for the manufacture of a Compound of formula (I) wherein Hal represents fluoro or chloro, and R
1
and R
2
represent, independently from one another, hydrogen or Hal; in which process a Compound of formula (II) is converted to a corresponding alkyl, fluoroalkyl or aryl sulfonic acid ester, which is then reacted with an alkali metal nitrite in the presence of a suitable crown ester in a polar non-nucleophilic solvent at a temperature of −10 to 50° C. to give the Compound of formula (I).
本发明揭示了一种制造式(I)的化合物的方法,其中Hal代表
氟或
氯,R1和R2分别独立地表示氢或Hal; 在该方法中,式(II)的化合物被转化为相应的烷基,
氟代烷基或芳基
磺酸酯,然后在极性非亲核溶剂中,在适当的
冠醚的存在下,与碱
金属
亚硝酸盐在−10至50℃的温度下反应,以得到式(I)的化合物。