Chemical Forums
Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: doublek1229 on March 12, 2010, 08:54:09 AM
-
In our organic chemistry lab with synthesized luminol. I understand the mechanism of the reaction, however I don't understand the purpose of triethylene glycol. Why would the reaction of 3-Nitropthalic acid and hydrazine require triethylene glycol? (It says it is "conveniently" carried out in a high boiling point solvent. Also what does the Na2S2O4 do to the 5-Nitropthalhydrazide to convert it into luminol. Thanks for any *delete me*
-
In our organic chemistry lab with synthesized luminol. I understand the mechanism of the reaction, however I don't understand the purpose of triethylene glycol. Why would the reaction of 3-Nitropthalic acid and hydrazine require triethylene glycol? (It says it is "conveniently" carried out in a high boiling point solvent. Also what does the Na2S2O4 do to the 5-Nitropthalhydrazide to convert it into luminol. Thanks for any *delete me*
Why should any reaction require solvent?
What is the difference between 5-nitropthalhydrazide and luminol?
-
In our organic chemistry lab with synthesized luminol. I understand the mechanism of the reaction, however I don't understand the purpose of triethylene glycol. Why would the reaction of 3-Nitropthalic acid and hydrazine require triethylene glycol? (It says it is "conveniently" carried out in a high boiling point solvent. Also what does the Na2S2O4 do to the 5-Nitropthalhydrazide to convert it into luminol. Thanks for any *delete me*
The solvent is just there to control the temperature. When a solvent is refluxing, it is at its boiling point. I am not sure about the salt you mentioned. Do you have a reference to the synthesis?
-
The reason DEG is used as a solvent is because the temperature the reaction is carried is very high, and as a result, a high boiling point solvent is required, so that while the reaction is being refluxed, the solvent still remains there and it is not fully evaporated.
-
The TEG is just a solvent, other solvents should work, but that allows easy heating to high temps. The Sodium Dithionate is a reducing agent, which reduces the 3-nitro group to a 3-amino group. This could also be done with hydrogenation, tin or iron in HCl, or a variety of other reducing agents, but Sodium Diothionate is very safe and easy to use, with no heavy metals or major fire hazards. I did that reaction many years back myself. Gotta love glowing stuff. Do you oxidize the luminol with NaFe(CN)6 and hydrogen peroxide?
Bob