GB1215396A - Production of monothio-oxamic acid compounds - Google Patents

Abstract

1,215,396. Monothio-oxamic acid compounds. BADISCHE ANILIN- & SODA-FABRIK A.G. 19 April, 1968 [21 April, 1967], No. 18623/68. Heading C2C. Monothio-oxamic acid amides of general formula where R<SP>1</SP> and R<SP>2</SP>, which may be the same or different, may be aliphatic, cycloaliphatic, araliphatic or aromatic, or R<SP>1</SP> denotes such a radical and R<SP>2</SP> denotes H, or R<SP>1</SP> with R<SP>2</SP> and the adjacent nitrogen may be a heterocyclic ring, and R<SP>3</SP> may be the radical -NH 2 or -OR<SP>4</SP>, where R<SP>4</SP> may be H, aliphatic, cycloaliphatic, araliphatic or aromatic, are prepared by reacting a haloacetic acid compound of the general formula where R<SP>1</SP>, R<SP>2</SP> and R<SP>3</SP> have the same meaning as above, R<SP>5</SP> may be a halogen atom, R<SP>6</SP> and R<SP>7</SP> may be H or halogen, with elemental sulphur and an amine having the general formula where R<SP>1</SP> and R<SP>2</SP> have the above meanings, in the presence of an acid-binding agent which may be identical with the amine, the amounts of amine and acid-binder being selected so as to favour the production of the desired product monothio-oxamic acid amide as compared to the undesired monothio-oxamic acid amide. The free haloacetic acid may be replaced by a salt of a haloacetic acid with an alkali metal, alkaline earth metal, unsubstituted ammonium or substituted ammonium cation and the process may be carried out in an inert organic solvent, e.g. alcohols, ethers or aromatic hydrocarbons at a temperature of 20-200‹ C., and preferably 50-150‹ C. Acid-binding agents such as tertiary amines, inorganic bases such as alkaline earth metal oxides, hydroxides or amides, alcoholates or salts of polybasic acids may be added to bind the acid present in the reaction, e.g. haloacetic acid as starting material or hydrogen halide formed.