Sciencemadness Discussion Board

Naphthalene Reactions

kyro8008 - 28-2-2006 at 00:45

I recently bought some naphthalene moth balls and when I get around to it I will purify them using sublimation.

I know you can nitrate naphthalene and it undergoes sulphonation reactions. Unfortunately I have only 40% nitric acid and 92% sulphuric acid so as far as im aware neither of these two processes are feasable for me. I also think it undergoes friedel-crafts type reactions, but I lack anhydrous aluminium chloride(on my todo list), and I dont have any chloroalkanes - could chloroform be used? - I would imagine it would be messy, would you get repeated substitution products because of the 3 chlorine atoms?

I was wondering if naphthalene undergoes any other reactions that are "easy" to do and use fairly common reagents as I would love to make another compound from it.

Thankyou in advance.

garage chemist - 28-2-2006 at 03:14

92% sulfuric acid is suitable for all processes calling for concentrated acid. A 6% difference in concentration can maybe lower the yield a bit, that's all.
From the naphthalenesulphonic acid, you can make naphthol (by fusion with NaOH and acidification of the reaction mix) which is useful in the synthesis of azo dyes.

Your 40% nitric acid can be upgraded to 68% nitric acid by simple distillation through a column (a simple vigreux is sufficient) while monitoring the temperature at the top of the column. Water comes over first, and then at 121°C (I think) the 68% HNO3, which is collected in a separate receiver.

From nitronaphthalene you can make naphthylamine, this can be diazotised and also used for azo dyes.

mantis - 28-2-2006 at 07:22

Quote:

could chloroform be used

maybe not, because Chloroform has not that ionic character, caused on the 3 Cl-atoms that stabilize themselves.
If it works, it will yield a CHCl2-gruop.

unionised - 28-2-2006 at 11:48

Chloroform certanly gives the FC reaction with benzene. IIRC naphthalene is more active but the steric hinderance might be a problem. Still needs a catalyst.

runlabrun - 28-2-2006 at 20:47

you can also make phthalic acid via oxidation of napthalene by permangenate.
Check out this thread esp -->
https://sciencemadness.org/talk/viewthread.php?tid=4752

And these others on phthalic acid and anhydride from napthalene -->
https://sciencemadness.org/talk/viewthread.php?tid=1726
https://sciencemadness.org/talk/viewthread.php?tid=1115

sparkgap - 1-3-2006 at 10:40

If any one of you will be making naphthylamine, do keep in mind that both isomers are confirmed or suspected carcinogens. Proper protection is an absolute must. :D

sparky (~_~)

Vitus_Verdegast - 5-3-2006 at 08:34

EP0027400

"Process for the manufacture of 1,4-naphthoquinone by oxidation of naphthalene by means of cerium (IV) salts in solution in an aqueous acid medium, characterised in that naphthalene, in pulverulent state, is put into suspension in the ceric salt solution by means of a dispersing agent, and that the 1,4-naphthoquinone obtained is separated from the aqueous medium."


note: the above patent is written in French

Cerium(IV) oxide is used in ceramics, to polish glass, and to sensitize photosensitive glass.

kyro8008 - 7-3-2006 at 12:18

Thanks for everyones ideas, thats brilliant - (I found it particularly hard to find details for many of these reactions for some reason).

Sorry for the late responce, I have been very busy with university interviews and such, but have now finished. :) I think I might have finally found a source for concentrated acids and many common reagents in my local area, in which case alot of these reactions are within grasp. :)

Thanks again!