Benzimidazolyl-2-alkane-phosphonic acids

US4278791A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Artur Botta · Krefeld, DE
• Heinz-Joachim Rother · Krefeld, DE
• Gunther Teichmann · Krefeld, DE

Key dates

• Filing date: Dec 10, 1979
• Grant date: Jul 14, 1981
• Expiry date: Dec 10, 1999

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C23F11/1676
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A benzimidazolyl-2-alkane-phosphonic acid of the formula ##STR1## wherein R.sup.1 and R.sup.2 are identical or different and denote hydrogen, lower alkyl, phenyl, halogen, trifluoromethyl, nitro or lower alkoxy, or together form a fused-on benzene ring, PA1 R.sup.3 denotes hydrogen, lower alkyl or phenyl or benzyl which is optionally substituted by lower alkyl or halogen and PA1 A denotes a straight-chain or branched, saturated or unsaturated bivalent hydrocarbon radical with 1 to 15 carbon atoms, which can be substituted by phenyl which is optionally substituted by lower alkyl or halogen or by carboxyl or the phosphonic acid group, and its salt with an inorganic or organic base or acid, and a method of preparing the same by contacting an o-arylene diamine of the formula ##STR2## wherein R.sup.1, R.sup.2 and R.sup.3 have the meaning given above, with a phosphonocarboxylic acid of the formula ##STR3## wherein Y denotes carboxyl, carbalkoxy, carbophenoxy, cyano, carbamido or carbochloride, PA1 R.sup.7 and R.sup.8 are identical or different and denote hydrogen, lower alkyl or phenyl, or together can form a ring, by means of an ethylene or propylene bridge, and PA1 A' denotes a straigh…