反应详情

A solution of 4 g of 2-bromo-1,3,4 thiadiazole and 13 g of 1-[(2H)-1,3-benzoxathiol-5-yl methyl]piperazine in 200 ml of xylene and 10 ml of anhydrous dimethylformamide was refluxed for 3 hours. Then, the mixture was cooled, the crystals of 1-[(2H)-1,3-benzoxathiol-5-yl methyl]piperazine hydrobromide formed during the reaction were suctioned off, and the xylene filtrate was extracted several times with a 2 N solution of methane sulfonic acid. The acid layer was decanted off then rendered alkaline with an excess of potassium carbonate, and the raw base extracted with chloroform. The organic solution was washed with water, dried over dry potassium carbonate, and the solvent was evaporated off. There were obtained 8 g of an oily residue which was submitted to a high pressure liquid chromatography (Waters apparatus) in the system CH2Cl2 -methanol; 98-2.

1. temperatureThen, the mixture was cooled