[Graduateonjulyamin]

Hai everyone

I have syinthesised schiff base from salicylic aldehyde and tyrosine with NaOH as catalyst and ethanol as solvent.
I used sonicator for reaction at room temperature.
 after i comfirmation my product using IR, i found that the product was same structure as tyrosine.
What should i do?
Please i need your help

[sjb]

How did you determine your reaction was complete before working it up? I'm not sure the amine on tyrosine by itself would be that nucleophilic (consider that amino acids exist as zwitterions). What other reactions may have happened?

(Also changed the title to be a bit more helpful)

[Graduateonjulyamin]

The addition of Noah consider ed will The protonated tyrosine.
I added NaOH before salycilicaldehyde and make sure that pH solution higher than tyrosine's pI.

[rolnor]

I have worked with orto-hydroxy imines and I recall that they have a strong yellow color, did you se that?

[Graduateonjulyamin]

No,i have not.
My product is gray.
Is it mean thats not product?

[AWK]

Both, tyrosine and its sodium salt are insoluble or poor soluble in ethanol. Even with sonication you should expect a very long time for reaction. In both reaction, neutralization and Schiff base formation, water is formed. Try removal of water from reaction by an azeotropic distillation.

[Graduateonjulyamin]

Should i use another solvent?

[AWK]

You have very limited choose: methanol (does not form ternary azeotropes with water) or ethanol.

[rolnor]

No,i have not.
My product is gray.
Is it mean thats not product?

I would expect a yellow product. If I remember correctly, the product easily break down to the startingmaterial in water. Perhaps you should use a ester of thyrosine, then you have less problem with solubility and the product should be more stable?