I need some Decalin, you know the solvent. Decalin is like naphthalene but without all the double bonds, its like to hexane rings stuck together. Anyway I have heard a rumor that is is used OTC in turpentine substitute. That's turpentine substitute, not regular turpentine.

I would like to ask anybody and everybody to stop by their local hardware store (at your convenience of course) and check the label of turpentine substitute and see if it contains any Decalin. Thanks.

I could try and make some Decalin. I am tracking a few synths but they don't look all that promising. Starting with naphthalene, seems easy enough... dissolve in glacial acetic acid, no problem... add some platinum or rhodium, maybe a bit tough or pricy... add hydrogen to a pressure of 150 atm, aww shit! There is no way in hell I am doing a high pressure catalytic hydrogenation. I may have a few workarounds up my sleeve, for example you can do the same reaction to naphthalenol (moth ball alcohol) at 4 atm, but that requires adding and then removing the alcohol.
I have been thinking about trying a Benkeser Reduction. Never heard of it you say? Well I got lucky on this one. saw it in Merck by accident :) Seem I can use calcium metal in an amine solvent, like methylamine to completly hydrogenate naphthalene. Too bad methylamine has such a low boiling point, I'll need a freezing bath to do the reaction. Using larger or more substituted amines will not reduce all the way, rather there will be a double bond or two. Of course that double bond will be in such a place as to make hydrogenation necessary (low pressure at least). Stupid thermodynamics :(

I know, sounds like a lot of work to do this, but I am limiting myself to a special criterion for OTC only applications. Making Decalin seems so easy yet so hard... When I finish my paper everybody can read all about it.

I assume the decalin is intended for some "higher" purpose?

And what may that be? :confused:

can't you use Ni as a catalyst? i have a vague memory of it being used in the hydrogenation of arenes...
30atm, 300*C, Ni powder catalyst and H2 pumped over it is used to hydrogenate benzene according to a book i've just tooke out my school bag....30atm must be a hell of alot easier to get than 150!
can't see why the same process wouldn't work on napthalene... but then i don't know much about aromatic chemistry <img border="0" title="" alt="[Frown]" src="frown.gif" />

As a higher boiling point solvent for Grignard reactions.

Don't you need an ether solvent for Grignards? Like Dioxan or THF? I always thought they were necessary to stabilize the grignard.

Usually, yes, but in this case I have a published ref that says neither ether nor THF will work, and Decalin is specificially requested. I know ether won't work because Grignards with chlorine require more vigerous conditions, but I don't know why THF dosn't. I intend to try THF anyway.

I also thought of using a nickel catalyst, but abandoned that line of reasoning. Nickel has far lower activity at lower pressure and with more highly substituted aromatics. Nickel can remove a few double bonds, but it will require enormous pressure for that last double bond (the one the connects the rings) for it is just stabilized too much. The only way to avoid the pressure is to use a more active cat like platinum or better still rhodium. I believe the presence of the hydroxyl (in naphthalenol) plays a role in the mechanism by allowing that final double bond a place to resonate thus allowing hydrogenation.

I even gathered up my nickels and was ready to dump them into acid (to begin making Raney nickel) before I realized the chemistry of hydrogenation with nickel would not work well enough.

<small>[ September 13, 2002, 05:35 PM: Message edited by: megalomania ]</small>

The Beckenser you specify is much like a Birch reduction, and you will have to run it for a long time to get a fully reduced compound.

Look for an electroreduction, with something like DMF as solvent. These are common, since the aromatic systems are easily reduced by systems that have lots of solvated free electrons.

PrimoPyro

Turps substiute is as common as muck here, and I've checked the back of many a bottle to try and see what exactly it is, but the most it ever says is "contains petroleum distilates".

A little digging on google and we have a few tid-bits:

UN number is: 1147

From <a href="http://ntp-server.niehs.nih.gov/htdocs/LT-studies/tr513.html:" target="_blank">http://ntp-server.niehs.nih.gov/htdocs/LT-studies/tr513.html:</a>


Decalin is used as an industrial solvent for naphthalene, fats, resins, oils, and waxes. It is also used as a substitute for turpentine in lacquers, paints, and varnishes; as a solvent and stabilizer for shoe polishes and floor waxes; and as a constituent of motor fuels and lubricants. Other applications include use as a paint thinner and remover, a patent fuel in stoves, a high-density fuel in submarine-launched cruise missile systems, and in stain removal and cleaning machinery.


The only product I managed to find was "Ceramichrome" - a cermaic overglaze/luster, which contains 5-15% decalin

<a href="http://www.ceramichrome.com/safety/glaze_msds/msds15.htm" target="_blank">http://www.ceramichrome.com/safety/glaze_msds/msds15.htm</a>

I finally made it to the hardware stores today with rather depressing results. I now doubt that Decalin will be listed by name in their products. Those companies are not very good at labeling their products. I did find a 3 lb container of 98% NaBr for $13, so it wasn’t a total loss. Oh, and I found it is cheaper to buy PVC pipe preparer instead of the adhesive for THF. I forget what the stuff is called, but it is used to get the plastic ready for something (this is not the cleaner which is a similar product, but which has no THF).

I have obtained a high temp little furnace meant for melting metal that I hope to use to make some calcium metal. I finally found a use for that bag of ice melting salt from Wal-Mart with sodium, potassium, calcium, and magnesium chloride. Originally I wanted to use this as a source of magnesium metal using an alcohol extraction process to get more or less a mix of calcium and magnesium chloride. Sodium and potassium chloride are not very soluble in alcohol, the common ion effect should keep them out when the other two chlorides are present. In fact it seems I salted out the water from my alcohol in my sample.
As it turns out the presence of calcium mixed with magnesium will be good as the melt point will be lower. I had hoped to remove the calcium by adding the mixed metals to water whereupon the calcium would react. Now I can use the mixed metal in the Benkeser Reduction, hoping that the magnesium doesn’t react, and collect the pure magnesium metal.

</font><blockquote><font size="1" face="Verdana, Arial, Helvetica">quote:</font><hr /><font size="2" face="Verdana, Arial, Helvetica"> have obtained a high temp little furnace meant for melting metal that I hope to use to make some calcium metal. I finally found a use for that bag of ice melting salt from Wal-Mart with sodium, potassium, calcium, and magnesium chloride.</font><hr /></blockquote><font size="2" face="Verdana, Arial, Helvetica">I do hope you will write about your metal production experiments whether you are successful or not. In theory, it is fairly trivial to produce alkali or alkaline earth metals (at least small quantities) from their chlorides or mixtures of chlorides. In practice, I have not yet met anybody who claims to have done this successfully (apart from tiny beads of metal, hardly useful quantities).

Also, might you elaborate on the nature, source, cost, and properties of your small furnace? Such an item could be generally useful to the experimentalist of limited means, especially if it can achieve high temperatures.

Why most certainly I will carefully document all of my experiments. I have heard good things and bad from a varity of sources about the success of the reaction, but I am confident I can make it work. The furnace is actually my uncles, he used to do metal casting and such, so it is up at the manner house. The making alkali metals is actually a subproject I have been meaning to try. Now that I have a new 4.1 megapixel digital camera to play with I can take many wonderful pics. As soon as we find the thing (its packed away *somewhere*) I will elaborate furthur. If that fails there is also a kiln.

I got a new Aldrich catalog today, Decalin is $50 a liter! Bah, I was under the impression that is was cheap. I hadn't bothered to look it up in any of my other catalogs yet.

I have been thinking about trying the Benkeser Reduction with ether. I may have to run the reaction for several days to get that last double bond, and using methylamine means a constant cold bath for days. I could rig a sealed system, but it seems to me that dissolving everything in ether would be much more conveniant and cost effective.

The decalin they sell is pure, so is expensive. Any analytical grade reagent is expensive. The fact that it cost 50 bucks doesn't mean that the decalin is expensive in general, in my oppinion.

If there is anyone else interested in isolating alkaly metals and other interesting elements (phosphorus) we may start a new project. One of my wildest dreams is to have most of the elements in vials. And I want to isolate barium, calcium, strontium, caesium (this one is a bitch as it's compounds are very expensive), and some other metals in general. I am planning to produce sodium in large quantities in order to use it as a reductor agent for calcium, barium, and other metal compounds.

Mega, I found in one of the MOA books (is the FTP <img border="0" title="" alt="[Wink]" src="wink.gif" /> ) a method for obtaining liquid chlorine, by closing in a glass tube some chlorine hydrate and by heating the tube. The hydrate will be decomposed and you'll get water and liquified chlorine by the means of pressure. A nice experiment; it worth a try, isn't it ?
It's funny to see in these old books how they supposed that mixing iodine with some fluorine salt will release fluorine (actually it was a compund between the two halogens). There are lots of such mistakes but on the other hand there are lots of nice experiments too which are no more encountered in our chemistry books.

Liquid chlorine will be produced from the high pressure produced when the chlorine hydrate decomposes, if that is, the phial doesnt explode which mostly as I recall, they did. I bilieve this was how chlorine was first liquified by Faraday in 1820, the product was a few 'oily' drops in the liquid of the second arm of the tube cooled in a freezing mixture. The drops 'vanish' when the phial is opened with the high pressure chlorine doing what is expected. Ammonia can be liquified in a similar way, I bilieve Faraday had got into the habit of setting the experiment up and then going away for a drink at the local pub. The result when he got back was usually the fragments of exploded tube. If you are after useful amounts of liquid chlorine by a safer modern method, a peltier pump, all solid state, will produce temperatures as low as -50C when powered and insulated/heatsinked properly. I hope to have access to the ftp, alas hotmail reports his email as full, hopefully this will be resolved soon. I am fascinated by old methods of chemistry and I am interested in making an element collection myself. I have a lot of advice from personal experience of making sodium but this isnt the thread for it.

On the subject of decalin wiser minds than mine have suggested the following:-
Napthalene in isopropyl alcohol at reflux will be reduced to decalin by hydrogen with a platinum black catalyst at atmospheric pressure. Flush out the air first several times with welding nitrogen (for example). Burn off the excess hydrogen. A good bubbler, eg fritted disk is essential. This method has been used successfully.

To make platinum black you can dissolve a few cm of platinum wire in aqua regia, evaporate, dissolve in isopropyl alcohol and reduce with hydrogen. Palladium coated beads from a car catalyctic convertor should work. Avoid rubber in all connectors/stoppers as the sulphur content will poison the catalyst. Use neoprene or silicone.

Most dissolving metal reductions fail becuase the reaction gets stuck at the disubstituted benzene stage, which is vastly harder to hydrogenate than even benzene. We cant comment on the calcium in amine solvent method.

From everything I have read about catalytic hydrogenation it requires high pressure. This is the reason I focused my efforts on the alkali metal reduction route. Your words that a hydrogenation can be done at atmospheric pressure are encouraging. I suspect it would be easier to prepare a suitable platinum catalyst than to obtain calcium metal and methylamine in ether solvent.

It makes little difference to me what route to use, but I am constrained by the parameters of my study. All materials must be OTC only. The information is intended for the lay audience, or for the not to distant future when the law tries to ban even more chemicals. Both routes are complex indeed, but if I provide enough information I hope anyone will be able to reproduce them.

Perhaps, since you seem to know your science Marvin, you may know of other alternative solvents to conduct the Grignard reaction in. That is the reason for the Decalin. I originally wanted to use the obvious choice of ether as the solvent. As I later found out through literature study and confirmed with organic chemist, ether has too low of a boiling point to sustain the higher reaction temperatures needed to initiate a Grignard with a chlorinated substance.
Bromines and iodines are easier to react, chlorine requires more heat. THF was the next choice, but I found a reference that said THF was found “generally unsuitable” for the reaction. I am not sure what that means exactly. At the same time I found my OTC route for THF synthesis was flawed anyway. It involved a Grignard reaction of an epoxide with a vicinal halohydrin, namely chloroethanol, which turns out can’t be done as the proton on the alcohol prevents the reaction.
The reference specifically requested Decalin. I do wonder if the double bonded version, a-9,10-octalin or something like that, would work just as good. It was my understanding that you needed an ether to assist in a Grignard. Theory always seems to be contradicted by reality in chemistry.

This has all been good fun for me. I enjoy the challenge of using completely unpopular and frivolous routes to synthesize chemicals that the scientific community regards as trivial to obtain. Of course those that don’t belong to the community get nothing, so it is for them that I work so hard to please.
On that note I could still use some help making THF. I don’t like the industrial methods for some reason… My current aim involves preparing 1,4-butanediol which could make THF via a condensation reaction. I can still use chloroethanol, but I have to add a protecting group to the alcohol. Using chlorotrimethylsilane would be an easy quick way of doing just that. Chlorotrimethylsilane is not an OTC chemical though. I don’t suppose anyone knows how to make this stuff? Have not found very much about its synthesis.

a_bab, you might be interested in my notes on phosphorous production (if I can find them). I have been entertaining ways of getting the stuff from triple superphosphate fertilizer, TSP cleaner, and bone meal. All three of these things are available in most hardware stores. I don’t need any phosphorus, but if the distinguished gentlewoman from Kalifornia senator Feinstein doesn’t like it that is reason enough to make sure everybody knows how to make it themselves. Tell me, does your method of sodium preparation happen to involve sodium carbonate mixed with charcoal and chalk heated high enough to release the metal?

No Mega, it doesn't. I am aware of the dangers using this method (formation of explosives superoxides, and peroxides at least in the potassium case). I want to do it by the hidroxide electrolysis.

To stay on topic, what about determining WHY other solvents are not suitable for the Grignard reactions, but decaline is ? In this way you may extrapolate other solvents. It sould be something about Mg reactivity, I guess (in decaline it'll be inert).

Actually I was given to understand that it is the spare electron pairs on the oxygen of ethers that assists the reaction. Ethers are also quite inert under Grignard conditions. I am not sure, but it could be that the mechanism is not well understood. I have the theory of it in a lab book upstairs somewhere...

What temperature are you looking to obtain? You know glyme or diglyme or tetraglyme might be what you are looking for as for properties. Tetraglyme boils over 200C IIRC. Check Chemfinder.

As for Grignard Reactions with chlorides, please give more details. Is the chloride aliphatic or aromatic? Are you reacting the Grignard Adduct with the chloride, or preparing the adduct from the chloride to react with something else?

Ultrasound is the Grignard's best friend. Grignard Reagents of the insanely stable chlorobenzene have been prepared by using ultrasound. Also, using Reike magnesium often helps VERY much. Reike magnesium is Mg made by reduction of MgCl2 with potassium metal, and this produces and ultra-reactive magnesium.

I recently made a thread at the Hive about Solvents for Grignard Reactions and stability, that went largely unnoticed. I can copy it to here if you like. The mechanisms of Grignard Reactions are very well understood.

You can also use a crystal of iodine to initiate grignard formation, or addition of catalytic 1,2-dibromoethane.

As for catalytic hydrogenation, there are many atmospheric pressure applications, and not all use platinum and palladium. Research Urushibara Nickel, and Catalytic Transfer Hydrogenation (CTH) with nickel and ammonium formate as a hydrogen donor. Very powerful reducing systems that are amazingly selective based on reaction conditions.

P.S. I forgot to say that there are reports of using trialkylamines (freebase form) in nonpolar solvents like toluene to assist in Grignard Formation. The lone pair of electrons on the nitrogen in tertiary trialkylamines (Dimethylaniline was specifically cited, I wonder about the cheaper triethylamine) act in the same manner as the lone pairs from oxygen ethers.

PrimoPyro

<small>[ September 28, 2002, 07:47 PM: Message edited by: PrimoPyro ]</small>

I thought for a long time about solvents, and it wasnt until I woke up I remebered diglyme. PrimoPyro has quite neetly beaten me to it though (I look forward to reading his full solvent list) so I can only add a few trivial details. Diglyme is CH3-O-CH2CH2-O-CH2CH2-O-CH3 which Ive written like that for ease of thinking, mainly mine. It can presumably be made from ethylene glycol and methanol and has a boiling point of 162C, only about 20 degrees below the lowest boiling isomer of decalin (THF is 120C below not much better than ether). Since its a polyether it might be a better solvent than decalin for the grignard so the slightly lower temp might not make a difference. I dont know of an OTC use for it, and since you are likley making it yourself you might try making the ethyl version instead, to push up the boiling point a bit. Some simple web searching revealed butyl diglyme to be a good solvent for grignards of chlorine and has a bp over 250, but not really easy for OTC. Id put my money on diglyme or ethyl diglyme if I was looking to replace decalin.

I think making decalin using the car catalyctic convertor beads could work well, though I dont know how much new cats cost, palladium coated beads could have a lot of other uses though in experiments. Decalin does have one advantage I can see, it shouldnt dissolve any water and this leads to something else Ive been thinking about, how are you going to dehydrate the solvents/reagents. Ether is normally dehydrated with sodium wire and I'm not sure CaO for example will quite cut it.

My final thoughts on this, is this is hell of a lot of trouble just to use a chlorine grignard, is the alkyl chloride you want to use OTC?

Phosphorous can be made much more easily from phosphoric acid or ammonium phosphate, which form glassy metaphosphoric acid (HPO3)n on strong heating. Less hydrogen to lose as phosphine, no silica required, lower temperature for reduction with carbon, or if desperate for a low temp reaction, aluminium. Excess aluminium will form a phosphide so avoid this. White phosphorous is very toxic (used to be used as rat poison) make sure you understand the health effects and its properties so you can avoid problems, in addition to the copious amounts of carbon monoxide the carbon reduction produces. Making monoammonium phosphate should be easy from triple superphosphate and ammonium sulphate if you cant get it directly.

Ah-ha! It happens you've hit upon one of my pet interests: the production of elemental phosphorus from readily available starting materials. A quick visit to any Internet forum dedicated to methamphetamine production will reveal that the easiest way is simply to extract red phosphorus from the striker pads on match books. However, this method is tedious, expensive, and simply inelegant.

I have made a few attempts - all failures - to prepare phosphorus starting with a phosphate and carbon. The phosphate that I used was diammonium phosphate. I suspected, as you do, that it would be easier to reduce than a phosphate of a reactive metal. I used a vessel made from a steel pipe. One end was capped, and the other had a nipple with a copper tube going through it, sealed in place by furnace cement. The end of the copper tube dipped slightly into a jar of warm water. Using a large gas lab burner hooked up to a propane tank, outdoors, I was able to raise part of the tube to red heat. Many noxious gasses were expelled from the tube. I obtained no phosphorus, however. When I removed the nipple/tube assembly and directly heated the mass of charcoal and diammonium phosphate, I eventually obtained jets of flammable vapor from the carbon. I suspect they were phosphorus because of the odor of combustion and appearance of the flames, which reminded me of burning phosphorus (which I have seen on a small scale).

I made one other attempt with similar results. I simply can't apply enough heat to the tube with this burner to make the reaction practical. I've thought of trying again with aluminum powder instead, or trying to use charcoal and forced air for the heat source, but I haven't tried either yet. The condensed glassy mass inside the tube after the heat goes away is a pain to chip out. Hot water doesn't touch it. Maybe hot NaOH solution would?

If you've actually tried to make phosphorus yourself, I would enjoy hearing about the attempt.

In fact so far Ive not succeeded in making P yet. The main reasons were I was trying to make the reaction go in a pyrex vessal, quite a tall order. I think this will be possible with aluminium though it might well wreck it in the process. The whole furnace+clay rhetort buisness was what I was trying to avoid. I was given some advice by the same chemist I talked to about decalin coincidentally enough. He suceeded with a setup not a million miles from yours. Steel pipe, capped one end, reducer on the other small furnace setup fired with propane, 80+% yeild. Since you got as far as metaphosphoric acid, why bother chipping it out! just leave it in until the next try, provided all the carbon wasnt used up (If so that would point to a different cause of failiar, and I know your smart enough to do the math). Metaphosphoric acid is a polymer, which is why its so hard to dissolve, if you let it soak in water it will depolymerise and dissolve by itself, ending up as fairly pure orthophosphoric acid. The only risk you run is the pipe rusting, so dont leave it in contact indefinatly.

I plan to try that setup as soon as I can handle the phosphorous safely, splinters get everywhere aparently when you break it cold. I also plan to make the metaphosphoric acid in a seperate step, so there is no risk of excess phosphine production, and the rhetort will fit more phosphate/carbon in. Ive been advised not to dip the end up the tube in the water, for a start suckback could cause real problems with the steel rhetort at not much short of 1000C. Cool the copper tube with hot water for a better yeild, the copper tube shouldnt react *much* with it so that should be ok. Cool with cold water and you risk it jamming up with P. During the reduction you'll have so much carbon monoxide coming out you wont need to worry about air getting in. Did you attempt to insulate the steel pipe at all during the last attempt or were you just heating the tube? Firebrick insulation should vastly improve the temp you can get the pipe too. If the worst comes to the worst I suspect a charcol furnace with only minimal air flow will be required to make the reaction go very well. I wont be trying this for several months at least, I have too much on the go currently so tell us what happens when you next try. As an afterthought, I might try lampblack instead of charcol, then I shouldnt have to purify the product at all.

Good luck!

Hi Polverone,

This question is not directed at me, but allow me to oblige.
__________________________________________________ ________________________________________

“Also, might you elaborate on the nature, source, cost, and properties of your small furnace? Such an item could be generally useful to the experimentalist of limited means, especially if it can achieve high temperatures.”
__________________________________________________ ________________________________________

I made my own gas furnace. The Design was inspired by a book on pottery kilns
The inside has the volume of a shortened 20 litre paint can. (That’s what I used for the inner mould)

Making Raney nickel with this thing would be a cinch (although I bought my catalyst at the time) They say that freshly prepared R Ni catalyst is better.

I once wanted to cast an Alu ingot. ‘Used a home-fabricated 4 mm thick walled stainless steel melting pot.

Then I wanted to try how hot my new baby could get, as a result the stainless steel pot melted! (In honesty it must have also partially dissolved in the Aluminium) but I had a nice puddle of funny alloy in the bottom of my kiln that I had to pour out before it solidified!

The furnace was easy to make, but it takes some time. It’s based on castable refractory concrete, a squirrel cage blower, which blows through a tangentially inserted 35 mm stainless steel tube in the bottom. and a simple piece of 6 mm stainless steel tube, sealed at the end and drilled with a 1 mm gas orifice, that sticks though a hole as drilled through the big tube. Light the thing by throwing in a match and the blower does the rest. (gas flow is regulated using a cheap Taiwanese reduction valve) Uses about 1.3 kg of gas per hour, at full blast. Temp should be well in excess of 1400 degrees C. (Did not want to expose my thermocouple to the higher temps.)

Makes one hell of a noise though.

The thing could be scaled down by 40% without much loss in performance.

Estimated cost: less than 65 bucks US. (Depends if you want to make it more energy efficient and lighter by using fire blanket, like I did)

Building time: depends how nice you want to make it; but if you want something that is better than anything you can buy, it is quite a bit of work.

If you want to get more details, drop me a line

I would love to hear the details of your furnace. I myself am interested in building such a thing, but details are hard to come by.

Hi Megalomania

‘Been very busy with Other Things

‘Just read your post. This weekend, I will certainly take full measurements of the furnace and make some CAD drawings that ill GIF.

(I'm one of those who are about to purchase a digital camera too.......)

I’ll put the drawings + text on the ftp-site. (‘Hope to be able to access this myself sometime in the future)

Wonderful site you’ve got man, wonderful!

Snuk