Derivatization of cysteamine hydrochloride by benzaldehyde

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Derivatization of cysteamine hydrochloride by benzaldehyde


I want to derivatized the
Cysteamine hydrochloride by  Benzaldehyde. I just prepare the 10% solution  of benzaldehyde and add in to methanlic solution of  Cysteamine hydrochloride. The 200 ppm Cysteamine hydrochloridesolution I have to use. I inject the solution on HPLC but no peak was found except the benzaldehyde. What is reason behind this. SHould I introduce the NaBH4 soltion into his of I have directly use bemzoyl chloride to derivatized it.
I also want to know from u that what is basic priciple to derivatized the amine or amine salts.

Best regards


Dr. Analytical
Dr. Analytical's picture
Dear Praveen:

Dear Praveen:
Are you following a standard procedure for this reaction?  The reaction conditions are very important for all derivatization reactions.

Benzaldehyde and your amine will produce a Schiff base (C+N bond).  Benzoyl chloride and your amine will produce an amide (O=CNH).   These are not the same reaction.  Also, your amine is in the ionic form (NH4+).  It will be more reactive if you neutralize it with base to form the neutral amine (NH2).

For more information you should find some reference books for more details.  Some general information is also available on the internet, but you should study the chemistry before you try any more experiments.