mr_bovinejony - 27-11-2020 at 15:22
Here are 3 papers explaining this route but I need some help understanding what products are being formed. In one paper, there is a table that lists
the precursor and the named nitriles and aldehydes. In the other papers tho, the products arent named and are just called decarboxylated. The same lab
procedure is used in all 3 papers. So do I assume that in the papers not mentioning the product names that they are a mixture of the aldehyde or
nitrile? Or do I assume that the product is just a decarboxylated amino acid?
Attachment: J. Biol. Chem.-1960-Konigsberg-1341-5 (1).pdf (635kB)
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Attachment: J. Biol. Chem.-1957-Chappelle-171-9 (1) (2).pdf (493kB)
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Attachment: J. Biol. Chem.-1961-Stevenson-715-7 (1).pdf (382kB)
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AvBaeyer - 27-11-2020 at 19:13
There is quite an extensive literature base on the chemistry in question. Did you do a basic Google search on the reaction of amino acids with NBS?
You could plug each of your references into Google Scholar and follow up on citations and related papers to find additional information.
One thing that is important is that the pH of the reaction medium will be a critical determinant of the products formed, nitrile vs aldehyde. You will
find this information if you do a thorough search.
Also, sodium dichloroisocyanuric acid is an excellent reagent for conversion of amino acids to nitriles. I posted a procedure for the conversion of
phenylalanine to phenylacetonitrile which can be found at:
https://www.sciencemadness.org/whisper/viewthread.php?tid=76...
AvB
mr_bovinejony - 28-11-2020 at 06:41
Yeah I had started my search after reading the post about the dcca method. I had found two of these papers in the references of the 1961 paper, but
I'll do some more searching to figure out what the requirements are for each amino acid
JJay - 28-11-2020 at 17:35
One major issue in these sorts of reactions is whether the amino acid is monohalogenated or dihalogenated prior to degradation. Monohalogenation gives
aldehydes; diahalogenation gives nitriles. High temperatures and lower concentrations of the halogenating agent compared to the amino acid tend to
favor aldehydes due to faster degradation and less likelihood that any amino acid molecule will be dihalogenated. Lower temperatures and higher
concentrations of the halogenating agent tend to favor nitriles.