Process for the preparation of 1-amino-1,3,5-triazine-2,4(1H,3H)-diones

US4524205A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Gerhard Bonse · Neunburg vorm Wald, DE
• Reinhard Lantzsch · Leverkusen, DE
• Henning Dorr · Bensberg, DE
• Wolfgang Kreiss · New Martinsville, US
• Karlfried Dickore · Leverkusen, DE
• Klaus Ditgens · Wuppertal, DE
• Eckart Kranz

Key dates

• Filing date: Oct 21, 1983
• Grant date: Jun 18, 1985
• Expiry date: Oct 21, 2003

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D251/38
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for the preparation of a herbicidally active 1-amino-1,3,5-triazone-2,4 (1H,3H)-dione of the formula ##STR1## comprising in a first stage at a temperature from about 0.degree. to 100.degree. C. reacting an isocyanate of the formula EQU R.sup.1 - NCO (II) with an isothio semicarbazone of the tautomeric formulas ##STR2## in which R.sup.3 and R.sup.4 each independently is hydrogen, alkyl, cycloalkyl, aralkyl o alkyl, cycloalkyl, aralkyl or aryl, thereby to form a urea derivative of the tautomeric formulas ##STR3## in a second stage at a temperature between about -50.degree. and 0.degree. C. reacting the urea derivative with phosgene (COCl.sub.2) in the presence of an auxiliary organic base and in the presence of a diluent, at least about 2 mols of phosgene and at least about 2 mols of the auxiliary base being used per mol of urea derivative, thereby to form a 1-alkylideneamino-1,3,5-triazine-2,4(1H,3H)-dione of the formula V ##STR4## and in a third stage converting the 1-alkylideneamino group to a 1-amino group.