公开(公告)号：ZA9004430B

公开(公告)日：1992-02-26

申请号：ZA9004430

申请日：1990-06-08

Applicant: BASF AG

Inventor： MERKLE HANS RUPERT ,  HANS RUPERT MERKLE ,  FRETSCHNER ERICH ,  ERICH FRETSCHNER

IPC: C07D231/06 ,  C07D231/12 ,  C07D

CPC classification number: C07D231/12

公开(公告)号：ZA904430B

公开(公告)日：1992-02-26

申请号：ZA904430

申请日：1990-06-08

Applicant: BASF AG

Inventor： MERKLE HANS RUPERT ,  HANS RUPERT MERKLE ,  FRETSCHNER ERICH ,  ERICH FRETSCHNER

IPC: C07D231/06 ,  C07D231/12 ,  C07D

Abstract: Pyrazole and its derivs. (I) are produced by dehydrogenation of the corresp. 2-pyrazoline (II) with the aid of sulphuric acid in the presence of iodine or an iodine cpd. (III) at 50-250 deg.C. (II) is produced in situ in the reaction medium by reaction of glycerol or acrolein or a deriv. thereof with hydrazine or a hydrazine deriv.; amt. of (III) is 0.01-10 mol. equiv. w.r.t. (II) or the corresp. hydrazine; 30-99 wt.% H2SO4 is used.