eXcidium (Newbee)
05-13-04 06:21
No 506782
      More on Chemiluminescence     

Hi folks, I don't know if anyone is interested ot not, but I digged a book out and dipped into luminescence a bit longer.

It's not "hive" related, so sorry, just a bit of general chemistry knowledge (if anyone is interested)


The reaction

The reaction is a two step "one pot" one, and here's how it goes

1: Aryl Oxalate (e.g. bis(2,4,6-trichlorophenyl) oxalate) + Hydrogen peroxide + catalist -----> 1,2-dioxetane-3,4-dione + 2,4,6-trichlorophenol

2: 1,2-dioxetane-3,4-dione + Fluorophore Dye (http://www.semrock.com/Catalog/AllFluorophoresTable.htm)  -----> CO2 + Fluorophore + Light

Now with some pictures....

1:











Molecule: bis(2,4,6-trichlorophenyl) oxalate ("ClC(C=C(Cl)C=C1Cl)=C1OC(C(OC2=C(Cl)C=C(Cl)C=C2Cl)=O)=O")

 +











Molecule: Hydrogen Peroxide ("[H]OO[H]")

 ----->











Molecule: 1,2-dioxetane-3,4-dione ("O=C1OOC1=O")

 +











Molecule: 2,4,6-trichlorophenol ("ClC1=CC(Cl)=CC(Cl)=C1O ")



2:











Molecule: 1,2-dioxetane-3,4-dione ("O=C1OOC1=O ")

+ Fluorophore ----->











Molecule: Carbon Dioxide (" O=C=O ")

+ Fluorophore + Light


And how it's done :

A solution of ~0.3% H2O2  + a catalytic amount of NaOH in THF was added dropwise to approximately 8 mL of the diaryl oxalate + fluorophore in THF (~25ºC) in a test tube (open vial)

The emission is relatively short lived but since H2O2 is apparently limiting, a second and third dropwise addition of the oxidant yields additional bursts of light.

"Ipsa scientia potestas est."
 
 
 
 
    eXcidium
(Newbee)
05-13-04 06:36
No 506785
      Luminol     

Same Goes with Luminol :

Luminol (2,3-dihydrophthalazine-1,4-dione) + Hydrogen Peroxide  + NaOH (-OH) + Catalist ----->
3-aminophthalate + Light

H2O2 +











Molecule: Luminol (" O=C2NNC(C1=C(N)C=CC=C12)=O ")

 AND (base -OH + catalyst) ----->











Molecule: 3-aminophthalate ("[O-]C(C1=C(N)C=CC=C1C([O-])=O)=O ")

+ Light

"Ipsa scientia potestas est."
 
 
 
 
    hypo
(Hive Addict)
05-13-04 11:02
No 506817
      interesting,     

but i don't see the relevance to the subjects discussed here at all.

now if you're into 24h+ phosphorescence and make bright yellow glowing
pills, now _that_ would be cool. cool

http://www.animalyawns.com
 
 
 
 
    armageddon
(Hive Bee)
06-04-04 20:36
No 511477
      luminol chemoluminescence is cool to look at     

Well although it's absolutely NOT drug related chemistry - don't you know these moments when the chemist begins staring at a flask like a child 'cause something wierd/fascinating happens inside it? wink

- In case you would like to reproduce this "aah"-effect at any time: try the luminol reaction, preferably with a buffered basic solution and Cobalt(2)chloride or potassiumhexacyano(3)ferrate as catalyst (copper(2) salts work too), and you will be astonished by the beauty of this blue glowing light....cool

Greetz A

"..ein Trank von unterschiedlicher Farbe, in ihm ist Heilung für die Menschen."
 
 
 
 
    hest
(Hive Adickt)
06-05-04 15:54
No 511613
      Light     

In the oxalicester reation tre things is important. keep the mixture dry, use stronh H2O2 (90%) if you cant't get that use peroxide in ether (mix diethyletehr an hydrogenperoxide, shake, seperate the ether and dry it) Make it on demand, some etherperoxide will be generated over time, but they are not as dangeres as the literature indikate.
Iff yoy can get the original phenol (trifluro propy something) you can made lightsticks with are as good as them you buy in a shop (5L of this mixture looks damm god)
 
 
 
 
    armageddon
(Hive Bee)
06-10-04 22:00
No 512621
      ether peroxides ARE dangerous     

I wouldn't store ethereal H202 for longer periods - believe me, as soon as the ether becomes discolored, it becomes VERY instabile..

(like Zwitterion said time ago: "One of the all-around party favourites.." wink)

A

"..ein Trank von unterschiedlicher Farbe, in ihm ist Heilung für die Menschen."
 
 
 
 
    eXcidium
06-13-04 16:53
      Experiments
(Rated as: insignificant)
    
 
 
 
    armageddon
(Hive Bee)
06-13-04 17:05
No 513147
      a nice one     

The Luminol reaction

Two solutions are prepared:

A) 100mg Luminol are dissolved in 20ml 10% NaOH solution. This is then diluted to 200ml with water.

B) 500mg K3[Fe(CN)6] are dissolved in 20ml 5% hydrogen peroxide. (solution B should be prepared immediately before use)

In a dark room, pour the (freshly prepared) solution B into solution A - a green/blue glowing light is the result. The Chemoluminescence can be refreshed by adding small quantities of K3[Fe(CN)6]...

Greetz A

"..ein Trank von unterschiedlicher Farbe, in ihm ist Heilung für die Menschen."