Last week I tried the synthesis from nickel perchlorate (itself synthesized from commercially available nickel nitrate and soda, the precipitate was
filtered, washed and redissolved in perchloric acid) and aminoguanidine perchlorate (prepared from commercially aminoguanidine bicarbonate and
perchloric acid).
I´ve always used less than the theoretical amount perchloric acid, in both cases some insoluble carbonate / bicarbonate remained at the bottom of the
vessel even if stirred over night.
Then I decanted the solutions from the insoluble impurities, the aminoguanidine perchlorate solution was yellow. I combined the solutions by dropwise
addition of the nickel perchlorate solution to an excess aminoguanidine perchlorate solution and heated the reaction mixture until bubbles appear,
then hold the temperature for several minutes and let it cool again to room temperature.
No visible reaction, no precipitate, nothing even after two days.
Disappointing.
Maybe the solutions were not concentrated enough or maybe the heating was not enough? Maybe the bubbles were simple carbon dioxide instead almost 100
degree centigrade water vapors? I didn´t use a thermometer to check the temparature, this was a mistake.
Is this reaction so temperature and/or concentration sensitive that slight alterations lead to a zero yield?
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