VERFAHREN ZUR HERSTELLUNG VON 1-SUBSTITUIERTEN 5-CHLOR-4METHYLPYRAZOLEN
申请人:BASF SE
公开号:EP1320527B1
公开(公告)日:2008-08-13
US7002023B2
申请人:——
公开号:US7002023B2
公开(公告)日:2006-02-21
Method for producing 1 substituted 5-chloro-4 methly pyrazoles
申请人:——
公开号:US20040102505A1
公开(公告)日:2004-05-27
The present invention relates to a process for preparing 1-substituted 5-chloro-4-methylpyrazoles of the general formula I
1
with the meaning for R stated in claim 1, in which a 4-methylpyrazole of the formula II
2
is reacted with chlorine, the resulting mixture of monochlorinated and dichlorinated product is fractionated by distillation, and subsequently the dichlorinated compound is dehalogenated to compound II and returned to the reaction with chlorine.