The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 02, 2000
Filed:
May. 18, 1999
Clariant GmbH, Frankfurt, DE;
Abstract
The present invention relates to a process for preparing arylhydrazines of the formula R.sup.1 R.sup.2 R.sup.3 Ar--NH--NH.sub.2 (I) by reacting an arylhydrazinedisulfonate of the formula ##STR1## in which R.sup.1, R.sup.2, and R.sup.3 are identical or different and are H, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy, halogen or OH, Ar is phenyl or naphthyl, M.sup.1 and M.sup.2 are identical or different and are H, NH.sub.4, an alkali metal or 1/2 alkaline earth metal and R.sup.1, R.sup.2, R.sup.3 and Ar in the formulae (I) and (II) have the same meaning, with water and an inorganic acid at from 0 to 100.degree. C. in the presence of an inert organic solvent to give the corresponding arylhydrazine salt and treating the arylhydrazine salt with a base.