1 -Phenylbiguanide-p-sulfonic acid

Cu(H03SC6H4C2N5H5)2] Copper (II) complexes of 1-phenylbiguanide-p-sulfonic acid, 7 6 Cul, 6 3... 

Red-violet modification. A mixture of 2.05 g. (0.008 mol) of phenylbiguanide-p-sulfonic acid and 150 ml. of water is acidified with 1.5 ml. of concentrated hydrochloric acid (35%) and warmed to 60°. To this solution is added 1 g. (0.004 mol) of copper (II) sulfate 5-hydrate dissolved in 10 ml. of water. The resulting solution is then treated with dilute (12%) ammonia water drop by drop imtil the solution becomes just alkaline and the red-violet crystals of the copper complex separate. About 4 ml. of ammonia is required. The crystals are filtered, washed first with 100 ml. of water and finally with 15 ml. of ethanol, and dried in air. Yield 2.2 g. (93% based on copper taken). Anul. Calcd. for [Cu(H03SC6H4C2NsH5)2]-H20 N, 23.59 Cu, 10.71 H2O, 3.04. Found N, 23.66 Cu, 10.61, 10.64 H2O (loss at 90°), 3.0. 

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