METHOD OF PRODUCING 2(3H)-BENZOTHIAZOLONE AND CERTAIN DERIVATIVES THEREOF Russian patent published in 2011 - IPC C07D277/68 C07D417/06 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing 2(3H)-benzothiazolone. The method is realised by boiling bis-(2,2'-dimethoxycarboxamido)-phenyl disulphide with zinc dust for 7,5 hours in glacial acetic acid, followed by separating zinc salts, diluting the filtrate with ice water, filtering the crystalline product and washing said product with diluted HCl (1:1) and water and then drying on air and recrystallising from ethanol. The invention also relates to a method of producing 3-2-[2-oxo-1,3-benzothiazol-3(2H)-yl]ethyl-1,3-benzothiazol-2(3H)-one. The method is realised by boiling 2(3H)-benzothiazolone with 1,2-dibromoethane in acetone in the presence of K₂CO₃. Water is then added and the mixture is treated with diethyl ether, followed by washing the organic phase with 10% aqueous NaOH solution and water, drying with anhydrous potassium carbonate, removing the solvent and recrystallising from methanol. The invention relates to a method of producing 3-(2-chloroacetyl)-1,3-benzothiazol-2(3H)-one. The method is realised by boiling 2(3H)-benzothiazolone in anhydrous benzene with chloroacetyl chloride for 10 hours, then washing the cooled reaction mass with 2% aqueous NaOH solution, extracting with benzene, washing the merged extracts with water, drying with anhydrous calcium chloride and removing the solvent, followed by recrystallisation from chloroform.

EFFECT: improved method of producing 2(3H)-benzothiazolone derivatives.

3 cl, 4 ex