From: chideste@pt.Cyanamid.COM (Dale Chidester)
Newsgroups: sci.chem
Subject: Luminol Synthesis
Date: 26 Jan 93 18:15:34 GMT
Organization: UTexas Mail-to-News Gateway
NNTP-Posting-Host: cs.utexas.edu


Since there was some interest expressed in the chemistry of light sticks, etc.
I offer the following for whatever it's worth.


                 LUMINOL Synthesis and Reaction

        NO2                                      ONO   O 
        |                                         |   || 
       / \ _COOH                  NH2    heat    / \ /  \NH
      | O |_COOH           +      |      ---->  | O |    |
       \ /                        NH2           |   |    NH
                                                 \ / \  /
    3-Nitrophthalic acid       Hydrazine              ||
       mp 222 C                                        O
       MW 211.13

                               Sodium hydrosulfite  ||
                                Na2S2O4             ||
                                 MW 174.10          ||
                                                    \/

                                               H2N    O
                                                 |    ||
            Luminol (3-Aminophthalhydrazide)    /  \ /  \
                                   mp 332 C    |    |    NH
                                  MW 177.16    | O  |    |
                                               |    |    NH 
                                                \  / \  /
                                                      ||
                                                       O

                                           H2O2      ||
                                         K2Fe(CN)6   ||
                                                     ||
                                                     ||
        NH2                                          \/
        |
       / \ _COO-                Singlet            Triplet
      | O |_COO-   + hv <------ Excited   <-----   Excited  +   N2
       \ /                      State      slow    State
     Ground State


Luminol Preparation:
First heat a flask containing 15 ml of water on a steam bath.  Then heat a
mixture of 1 g 3-nitrophthalic acid and 2 ml of 8% aqueous hydrazine* in a
20x150 mm test tube over a free flame until the solid is dissolved.  Add 3
ml triethylene glycol and clamp tube in a vertical position over a micro
burner.  Insert thermometer, BOILING CHIP!, and an aspirator tube connected
to an aspirator.  Boil vigorously to distil excess water (110 - 130) Let
temperature rise rapidly to 215 C (3-4 minutes)  Remove burner and note time.
By intermediate, gentle heating, maintain temperature at 215-220 C. for 2
minutes.  Remove tube, cool to about 100 C (crystals may appear).  Add 15 ml
hot water and cool under a tap.  Collect light yellow granular nitro compound
by filtration.  Transfer nitro compound back to test tube (it need not be
cleaned) and add 5 ml of 10% sodium hydroxide solution.  Stir with rod.  To
deep brown-red solution, add 3g sodium hydrosulfite dihydrate.  wash solid
down walls with a little water.  Heat to boiling point, stir and keep hot
for 5 minutes.  Some reduction product may separate during this time.  Then
add 2 ml acetic acid, cool under tap and stir.  Collect resulting ppt of light
yellow luminol by filtration.  Filtrate will often deposit further crop of
luminol after standing overnight.

Luminol Solution:
Disolve luminol (0.1 - 0.2 g) in 10 ml of 10% sodium hydroxide solution and
90 ml of water.  This is Solution A.  Prepare Solution B by mixing 20 ml of
3% potassium ferricyanide solution, 20 ml of 3% hydrogen peroxide and 160 ml
of water.

Luminol Reaction:
Dilute 25 ml of Solution A with 175 ml of water.  Pour this solution and
Solution B together simultaneously into a funnel resting in the neck of a
large Erlenmeyer flask.  Swirl flask.  To increase brilliance, gradually add
further small quantities of alkalai and ferricyanide crystals.

If the ferricyanide is omitted, the reaction can be catalyzed by adding blood
dropwise to the reaction mixture.

* 8% aqueous hydrazine can be prepared by diluting 31.2 g of commercial 64%
hydrazine to a volume of 250 ml.

Hydrazine is a carcinogen.  Handle with care.  Wear Gloves and carry this
experiment out in a hood.  Do not attempt this experiment unless you are
trained in organic synthesis procedures.

Neither I or American Cyanamid take any responsibility for the accuracy of
the above or for the results of any attempt to perform the experiment
described above.  You're on your own!

------------------------------------------------------------------------
Dale H. Chidester, PhD           N3HAL      "Against ignorance, even the 
American Cyanamid Company                    Gods in vain doth contend."
Agricultural Research Divison                                     Goethe
PO Box 400,  Clarksville Rd.     Phone: (609) 799-0400 x2430
Princeton, NJ  08543-0400        Email: chideste@cyanamid.com 
------------------------------------------------------------------------