Metacelsus
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Kaiser ninhydrin test: what's the point of the cyanide?
The Kaiser ninhydrin test is used to detect primary amines. The test is based on the reaction of ninhydrin to form a purple-colored product. However,
the test also requires two other reagents besides ninhydrin: a solution of phenol and ethanol, and a solution of KCN in pyridine. The test procedure
goes like this:
1) Put sample in test tube.
2) Add ninhydrin solution, phenol solution, and KCN/pyridine solution.
3) Heat in boiling water bath for 5 minutes.
4) Check for color change.
It seems like ninhydrin alone would be enough to produce the color. What's the point of the other reagents (especially the KCN)?
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CuReUS
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| Quote: | | In the search for a more stable and soluble reducing agent we observed that potassium cyanide led to the formation of hydrindantin when added to a
solution of ninhydrin |
http://www.jbc.org/content/200/2/803.full.pdf+html
the reason for the choice of solvents is also given in that paper
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Metacelsus
International Hazard
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Thanks; that paper was very informative.
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