Yield:-

Reaction Conditions:

with triethylamine in dichloromethane;

Steps:

12 EXAMPLE 12

EXAMPLE 12 5-Chloro-2-benzothiazolinone-3-acetic acid (2.5 g) and triethylamine (1.4 ml) are dissolved in dichloromethane (25 ml). To the solution is added 1-methanesulfonyloxy-1,2,3-benzotriazole (2.2 g) at room temperature, and after 10 minutes, 1-(2-hydroxyethyl)piperazine (1.3 g) is thereto added. After allowing to stand at room temperature for 18 hours, the reaction mixture is washed with a saturated aqueous sodium hydrogen carbonate and then dried over magnesium sulfate. After drying, the solvent is distilled off and the resultig residue is crystallized from ethanol-ether. The crystals thus obtained are washed with acetone and dried to give 3-[4-(2-hydroxyethyl)-1-piperazinyl]carbonylmethyl-5-chloro-2-benzothiazolinone (1.3 g), melting point: 155°-156° C. The product is identified with an authentic sample by infrared spectrum.

References:

US4242507,1980,A