Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
Author: Subject: What would the procedure for Benzidine to aniline look like?
njl
Harmless
*




Posts: 10
Registered: 26-11-2019
Member Is Offline

Mood: 20 miles into bat country

[*] posted on 26-11-2019 at 13:33
What would the procedure for Benzidine to aniline look like?


Is is silly to assume a one step conversion in an acidic solution is possible?

Edit: On a tangentially related note, is there any immediate problem with substituting propylene glycol with regular glycerin in the isolation of terephthalic acid from PET plastic?

http://www.sciencemadness.org/member_publications/terephthal...

[Edited on 26-11-2019 by njl]
View user's profile View All Posts By User
DavidJR
International Hazard
*****




Posts: 777
Registered: 1-1-2018
Location: Scotland
Member Is Offline

Mood: Anxious

[*] posted on 26-11-2019 at 14:14


I doubt there is an easy way to break that carbon-carbon bond.

Also, be careful with benzidine, it is a very potent carcinogen.
View user's profile View All Posts By User
Boffis
International Hazard
*****




Posts: 1208
Registered: 1-5-2011
Member Is Offline

Mood: No Mood

[*] posted on 26-11-2019 at 15:04


Glycerin is not stable enough at high temperatures to replace ethylene or propylene glycol in the depolymerisation of PET.

If you can get benzidine surely you can get aniline! Benzidine is now highly controlled in most countries due to its known toxicity.
View user's profile View All Posts By User
njl
Harmless
*




Posts: 10
Registered: 26-11-2019
Member Is Offline

Mood: 20 miles into bat country

[*] posted on 26-11-2019 at 15:24


Thanks. I wasn't planning on using it in any particular reaction, just wondering if there was a known mechanism for the cleavage of that single bond between two rings. I've noticed that many similar compounds with two linked aromatic rings seem to be awfully toxic. Is there a reason Benzidine derivatives (and those of similar structures) are so nasty?
View user's profile View All Posts By User
draculic acid69
International Hazard
*****




Posts: 592
Registered: 2-8-2018
Member Is Offline


[*] posted on 26-11-2019 at 22:11


Quote: Originally posted by njl  
Is is silly to assume a one step conversion in an acidic solution is possible?

Edit: On a tangentially related note, is there any immediate problem with substituting propylene glycol with regular glycerin in the isolation of terephthalic acid from PET plastic?

http://www.sciencemadness.org/member_publications/terephthal...

[Edited on 26-11-2019 by njl]


Extractions and ire or explosions and fire has a video of decomposition of pet in glycol to get the terepthalic acid. If u watch his videos you'll get some good info.i think if I was doing it is try it in just water in a pressure cooker.the idea of adding glycol just to
have to deal with it later seems like a hassle that might not be necessary.watch the videos.
https://m.youtube.com/watch?v=JuvczYeM3kk
https://m.youtube.com/watch?v=uRTrjaAb4NA
https://m.youtube.com/watch?v=Zh0RK0an8f4
View user's profile View All Posts By User
draculic acid69
International Hazard
*****




Posts: 592
Registered: 2-8-2018
Member Is Offline


[*] posted on 26-11-2019 at 22:14


Also glycerine is more expensive than glycols.
View user's profile View All Posts By User
Pumukli
International Hazard
*****




Posts: 510
Registered: 2-3-2014
Location: EU
Member Is Offline

Mood: No Mood

[*] posted on 27-11-2019 at 00:01


One will get glycol anyway bacause the hydrolysis of PET produces ethylene glycol and terephthalic acid in equimolar proportions.

As for the toxicity of benzidine: my understanding is that the problem lies in the two p,p'-positioned amino groups and the distance between these groups. These groups can criss-cross link the DNA strands because they are similarly basic as the nucleotides (adenine, thymine, guanine, cytosine) in the normal DNA. The structurally damaged DNA causes cancers sooner or later.
View user's profile View All Posts By User
Metacelsus
International Hazard
*****




Posts: 2334
Registered: 26-12-2012
Location: Cambridge, MA
Member Is Offline

Mood: Double, double, toil and trouble

[*] posted on 27-11-2019 at 05:18


In particular, the benzidine is metabolically acetylated and oxidized to an N-hydroxy compound, which then forms a nitrenium ion. This can react with DNA. See: https://www.ncbi.nlm.nih.gov/pubmed/455295

Other aromatic amines can react similarly.




As below, so above.
View user's profile View All Posts By User

  Go To Top