


Ferbam Ziram Copper Salt _ 
* A, 
3 Fett ae 5 tat Det ( fo 
Ferbam reacts with thiols by a radical exchange mechanism. The final 
products are the corresponding disulfide of the parent thiol and dimethyl- 
dithiocarbamate. At pH >7, ferbam decomposes to give dithiocarbamate ions. 
At pH <5, it decomposes to dimethylamine and CS7. At pH 6 to 7, the nature 
of the buffer is important: ferbam is stable in acetate but decomposes in 
phosphate buffer to dithiocarbamate (1123). 
At acid pH, ultraviolet spectra showed that [(CH3)2NCS2] 2 was present. 
At higher pH, the spectra indicated the presence of (CH3})9-N-CS>5. In the 
presence of dilute acid, ferbam and ziram decomposed at a slower rate than 
did the sodium salt, with evolution of carbon disulfide. A secondary de- 
composition product in the form of an amine also formed, When the copper 
salt was tested, no carbon disulfide could be detected (897, 1407, 1474). 
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