MNK
Harmless
Posts: 11
Registered: 19-2-2008
Member Is Offline
Mood: No Mood
|
|
What exactl is ortho-chloranil?
I can already see the posts instructing me to google it so dont bother, I already have, and I've found nothing but complex articles discussing very
specific applications of the product/substance. What I'm hoping for here is a general discription of ortho-chloranil, and if possible, any information
relating to its purchase.
Thanks
|
|
|
ScienceSquirrel
International Hazard
Posts: 1863
Registered: 18-6-2008
Location: Brittany
Member Is Offline
Mood: Dogs are pets but cats are little furry humans with four feet and self determination! 
|
|
It is 3,4,5,6-tetrachloro-orthobenzoquinone
A quick look at this article should make it clear
http://en.wikipedia.org/wiki/Quinone
Buying it?
Tricky unless you have access to Sigma Aldrich and their ilk.
Apart from that you may get lucky and be able to order some from a photographic supplier that deals in raw chemicals if you can convince them that you
are into heavy DIY developing.
Oh and it is not cheap!
http://www.sigmaaldrich.com/catalog/search/ProductDetail/ALD...
[Edited on 3-9-2008 by ScienceSquirrel]
|
|
|
Nick F
Hazard to Others
Posts: 439
Registered: 7-9-2002
Member Is Offline
Mood: No Mood
|
|
Catechol + XNO3 + HCl, if you can't buy it?
|
|
|
ScienceSquirrel
International Hazard
Posts: 1863
Registered: 18-6-2008
Location: Brittany
Member Is Offline
Mood: Dogs are pets but cats are little furry humans with four feet and self determination!
|
|
| Quote: | Originally posted by Nick F
Catechol + XNO3 + HCl, if you can't buy it? |
He really needs a recipe for that.
The problem with organic reactions is getting a decent yield and isolating the product.
|
|
|
Ritter
Hazard to Others
Posts: 370
Registered: 20-6-2008
Location: Earth
Member Is Offline
Mood: Curious
|
|
To give you possibly an idea of what's involved, here is an outline of the synthesis of the para-isomer starting from hydroquinone:
| Quote: | . A process for the preparation of tetrachloro-1,4-benzoquinone from hydroquinone in the presence of an aqueous medium containing chlorine and
hydrochloric acid, which comprises the steps of:
providing an aqueous medium containing iron (III) ions as a catalyst, an anionic dispersant, and hydrochloric acid in a concentration of 20 to 37%,
said hydrochloric acid being provided in a 4 to 6 times molar amount based on the total amount of hydroquinone to be added in said process;
dividing said total amount of hydroquinone into space-time yield-improving portions and introducing a first portion of the hydroquinone into said
aqueous medium; introducing 1.5 to 2.0 times the molar amount, based on said total amount hydroquinone, of chlorine as a gas into the aqueous medium
at a temperature of from 20.degree. to 90.degree. C. in a first chlorine addition; adding the remaining portion of hydroquinone; introducing 1.5 to
2.0 times the molar amount, based on said total amount of hydroquinone, of chlorine as a gas in a second chlorine addition; holding the concentration
of the hydrochloric acid in the aqueous medium at 23-25% by addition of water; raising the temperature to 100.degree. to 107.degree. C. while
introducing additional chlorine gas at 1.7 to 2.5 times the total molar amount of hydroquinone in a third chlorine addition; and diluting the aqueous
medium with water to a hydrochloric acid concentration of from 20 to 22%.
|
Ritter
=============================
\"The production of too many useful things results in too many useless people.\"
Karl Marx
|
|
|
UnintentionalChaos
International Hazard
Posts: 1454
Registered: 9-12-2006
Location: Mars
Member Is Offline
Mood: Nucleophilic
|
|
There was quite a bit of discussion on the para isomer in energetics IIRC, since it was being looked into as a precursor for a tetraazide primary
explosive. I don't often read that forum so I do not remember how the synthesis went. I imagine the ortho isomer is nearly identical in preparation
but using ortho-benzquinone (oxidation of pyrocatechol perhaps) instead of the para isomer.
Department of Redundancy Department - Now with paperwork!
'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
|
|
|
Ritter
Hazard to Others
Posts: 370
Registered: 20-6-2008
Location: Earth
Member Is Offline
Mood: Curious
|
|
An older reference (Organic Reactions vol. 4, p. 316) gives the prep method as the oxidation of tetrachlorocatechol with nitric acid to give
an 81% yield. Ref: Am. Chem. J. 1907, 37, 11. Reference is made to running the reaction in either acetic acid or ethanol. The halogenated o-quinones
are described as being 'sufficiently stable.'
This patent gives a continuous lab-scale process for making o-chloranil from tetrachlorocatechol via chlorination of catechol & nitric acid
oxidation: http://www.pat2pdf.org/patents/pat4196132.pdf
[Edited on 3-9-2008 by Ritter]
Ritter
=============================
\"The production of too many useful things results in too many useless people.\"
Karl Marx
|
|
|
MNK
Harmless
Posts: 11
Registered: 19-2-2008
Member Is Offline
Mood: No Mood
|
|
Thanks guys, much appreciated
|
|
|
tapira1
Hazard to Others
Posts: 168
Registered: 9-10-2006
Location: Here!!!
Member Is Offline
Mood: 
|
|
Chloranil
Don't know what are you goung to use it for, but DDQ is a substitute in many processes.
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
