PrimoPyro (Hive Prodigy)
03-06-02 03:23
No 277497
      Range Of Applications For Catalytic Hydrogenation  Bookmark   

I wonder, just how many things will be reduced when catalytically hydrogenated? Please list anything that you know to be possible, that is not on this list, I would appreciate it very much. Thank you.

So far, I know one can perform these conversions with catalytic hydrogenation:

Alkene --> Alkane
Ketone --> Alkane
Aldehyde --> Alkane
Nitro --> Amine
Nitroso --> Amine
Nitroalkene --> Aminoalkane
Nitrile --> Aminoalkane
Imine --> Amine
Aryl Halide --> Aryl Hydride
Alkylamide --> Alkylamine

And I wonder, can one reduce carboxylic acids, or esters? Esters would either yield ethers or alhohols, and carboxylic acids would either yield alcohols or alkanes.

Are either conversion possible?

                                                   PrimoPyro

Vivent Longtemps La Ruche!
 
 
 
 
    foxy2
(Distinctive Doe)
03-06-02 05:37
No 277548
      Re: Range Of Applications For Catalytic Hydrogenation  Bookmark   

I think there is a way to catalytically reduce any organic molecule that can bee reduced.  Just a function of catalyst, temp, pressure ect. 

Make a Difference Donate Now!! (http://www.lp.org/drugwar/)
 
 
 
 
    Chromic
(Hive Addict)
03-06-02 05:46
No 277557
      Re: Range Of Applications For Catalytic Hydrogenation  Bookmark   

I think that reduction of an ester would cleave it to an alcohol and an acid, which would then be reduced to an alcohol. (no ether formation) If the conditions are fairly strong then the alcohol might go to the alkane.
 
 
 
 
    masterofpuppets
(Hive Addict)
03-09-02 10:30
No 279383
      Re: Range Of Applications For Catalytic Hydrogenation  Bookmark   

Carboxylic acids may be able to be reduced (although if they are on a structure with an amine group then I would doubt it).

Suicide is man's way of telling God, "You can't fire meI quit." Bill Maher, 1995
 
 
 
 
    Rhodium
(Chief Bee)
03-09-02 18:35
No 279564
      Re: Range Of Applications For Catalytic Hydrogenation  Bookmark   

In the abstract of  ../rhodium/archive/cooh-2-ch3.pdf they say that their method is the first known direct reduction of an aliphatic carboxyl function to a methyl group.
 
 
 
 
    PrimoPyro
(Hive Prodigy)
03-09-02 19:22
No 279589
      Re: Range Of Applications For Catalytic Hydrogenation  Bookmark   

Thanks everyone for your replies.

Thinking of building a nice catalytic hydrogenation chamber, or two. One small size (microscale) and one macroscale. Wanna try and reduce ephedrine with pressurized catalytic hydrogenation with Uru-Ni.

Woudnd't mind suffering through the high yields of nitroalkene reductions with catalytic hydrogenation, either....

                                                  PrimoPyro

Vivent Longtemps La Ruche!
 
 
 
 
    epistemologicide
(Hive Bee)
03-10-02 10:42
No 280026
      Re: Range Of Applications For Catalytic Hydrogenation  Bookmark   

swim hopes to build from the adams cat synth off rhods page, and has a mechanic that can step by step explain the process of the equipment needed out side the chemistry of the synth,

swim hopes to have it written when done ala worlok style for you all,

we need more worlok profanatory  irreverence, style write ups!!!



hatred of ontological wastes, and the marathon!!!!
 
 
 
 
    Organikum
(Newbee)
03-10-02 19:58
No 280168
      Re: Range Of Applications For Catalytic Hydrogenation  Bookmark   

perhaps useful:
So there was a lot talking on "burst pressure" and all this lately I looked up a few specifications on pressurized devices.

!!!THIS IS ONLY VALID FOR EUROPE AND COUNTRIES FOLLOWING THY "DIN"!!!

By law every pressure device, if gaseous or liquid pressured has to withstand a pressure 8x as high as nominal before burst. Burst must not be in an shrapnel way but by opening without parts flying around. This has to be guaranteed till end of thy devices lifetime.

Thats good news, so I dont advise anybody to go to more than a half of thy limit, I would recommend to use some standard pressure vessel manufactured by industry and to do no modifications at all if possible.
think: Coca-Cola, beer, water filters, compensation vessels of heating systems, hydraulics, pneumatics, quickficks,


Stay safe, if ya must, hurt yaself nobody else
ORGY

"I hope I'm becoming more eccentric. More room, you know.
 More room in the brain."
 
 
 
 
    PrimoPyro
(Hive Prodigy)
03-10-02 20:07
No 280169
      Re: Range Of Applications For Catalytic Hydrogenation  Bookmark   

Try this one: Nitrogen propellant tanks for paintball guns.

They withstand up to 4000psi. The typical charge pressure is 3000psi. Don't give me any shit about units, that's what's on the tank. Just remember that one atmosphere is ~14psi, and that's all it takes for you to realize that thse will not burst at hydrogenation pressure: ~3 atmospheres.

They are epoxy-resin wrapped glass tanks, and have removable pressure valves at the top. The valves have built in pressure guages that go up to....you guessed it, 4000psi. They have a semirounded bottom, and since they are glass, I suspect that if I stirbar were introduced inside the unit, it would operate just fine.

Remove the cap, introduce your reactants, re-affix the valve and guage, attach the hydrogen tank, and "charge" the tank up to a mere 45psi from a hydrogen tank instead of nitrogen.

                                                    PrimoPyro

Vivent Longtemps La Ruche!
 
 
 
 
    zed
(Newbee)
04-22-02 05:23
No 300018
      A cannon, to kill a mouse?  Bookmark   

For reasons of my own, I'm not going to be to be incredibly helpful here. That being said, working with high pressures and temperatures, lacks elegance. And, a 4000psi reaction vessel breeching, may convert your lab into an empty space.

Since, you probably rent, this may not concern you much. The concern is that you may be in said lab, when it is reduced to splinters.

For most of the purposes that you might wish to use hydrogen for, pressure and heat really are not required.

If you want keep your name out of the newspapers, do a little homework on the method of Brown & Brown. It might give you some interesting ideas. Think on it!

A Bodacious Hydrogenator, will impress your friends and fellow bees. It will be even even more impressive to Johnny Law, should he stumble onto it. You will be tagged as a "Real Pro".

It would be much better for you, if you had a tank of H2, a tank of O2, and a torch or some other device that might concievably use those two items as fuel. With your small amount of lab equiptment, far away, it could be argued, that you acually weld sometimes.

Try to be a minimalist! You may be able to pare down your lab, to just a few bananna boxes of really critical stuff, that you can safely stash, far away. When you can, use Mason jars, gallon Pickle jars, or other cheap disposables. Dump 'em when you are done. If you are only running one..... capitalist type reaction sequence....You may find you really need very little stuff....to produce large amounts of product.

Cop talk:

" OK, we swabbed the floor; It was negative". "There wasn't any glassware, or equiptment we could find, and no drugs or chemicals". "So, listen up, dickwad, as much as we would like to beat you to death on the spot, we gotta let you go". " Your innocent act doesn't fool us, we are gonna catch you and crucify you; next time you won't be so lucky".

Rough talk, but better than hearing the old "You have a right to remain silent".

So, anyway, Hydrogen is good. Hydrogen is sweet, fast, remarkably clean, and pretty easy to work with, once you learn the ropes. And, learning how to use Hydrogen, may allow you to throw most of your glassware, and nasty reagents away.
 
 
 
 
    PrimoPyro
(Change my Title Back!)
04-22-02 05:50
No 300037
      Read it again.  Bookmark   

You misunderstand my last post.

My intention was to illustrate that I most definitely to not fear such a vessel as a high pressure glass nitrogen tank rupturing in only one use, when it is usually operated storing nitrogen in upwards of 4000psi, and I would be using it at a mere <50psi and no heat. After one reaction, the bottle goes to the trash heap.

As for your sermon on why use hydrogenation, I can only say that most of it, I disagree with, and the rest, is well off topic. I thank you for sharing your opinion, and I have listened, and simply disagree with much that has been stated as you chose to do so.

                                                   PrimoPyro

Vivent Longtemps La Ruche!
 
 
 
 
    hest
(Hive Bee)
04-22-02 12:45
No 300130
      Hydrogen hmmm  Bookmark   

If somone has red my post the last 30 dayes, they no abouth my 'luck' with a parr shaker. Greath for turning nitopropenes into oximes (yak yak)
Greath for turning nitroalkanes into oximes (more yak yak)
Greath for reducing aromatic nitrogroups, and dob./trip. bonds (but I guess that is not so important at this place :)
So, I don't find cat. hydrogenation under presure that usefull. 
 
 
 
 
    zed
(Newbee)
04-26-02 03:34
No 301443
      Thank you.  Bookmark   

You are quite correct; I was mostly off topic. I have always obsessed about not getting caught.....I tend to preach!

However, for the reduction of nitro-alkenes, you may not even need 50psi. As you are aware, hydrogenations are pressurized to take advantage of Henry's Law.

Doubling pressure....Doubles the soluability of gas in solvent. Thereby increasing reaction rate.

A very active catalyst, like that produced from NaBH4 and Chloroplatinic Acid, will often accomplish reductions well, at STP.

The reduction of nitro-propenes is one such reaction. Also notable....Regarding heat, at 50psi, the reduction of nitro- propenes, is quite exothermic...It produces it's own heat; It may require cooling.

Also, for some reason, a few people seem nervous about hydrogenating Nitromethane. They like to introduce it gradually dripwise for reduction. Then, when it is completely reduced to methylamine, they proceed to add P2P or whatever other ketone they wish to reductively aminate. This sequence avoids wasteful side reactions.

May your reactions never go too exo...............zed
 
 
 
 
    ClearLight
(Hive Bee)
04-26-02 06:17
No 301501
      a few questions a few answers  Bookmark   


CL has some experience with pressure vessels, as he really IS a rocket scientist!  In designing AL+NH4KCl04+HTPB motors, I usually work with a 1000 psi pressurization. T-6 aluminum in 1/4" wall will handle that up to about 30-40kpsi.

  There are numerous references that you can get for the various strengths, just look for people selling stainless pipe on the net and they'll usually have hoop strength in the specs, or tell you how to read the codes...

  Omega electronics will sell you a calibrated pressure sensor, along with a threaded sapphire snubber so you can get a reading on it along the way... we used these to monitor chamber pressure and they were impervious to the combustion products.

  Having a relief valve is a nice way to channel overpressures, make sure it's pointing in a safe direction into something that can catch your contents.

juz my 2x10E-2 cents worth...


 
 

Infinite Radiant Light - THKRA
 
 
 
 
    ClearLight
(Hive Bee)
04-26-02 06:20
No 301504
      Raney-Nickel??  Bookmark   

I used the search engine on this goodie, and got no hits.. maybe a sp error, but is this useful for cat. hydrog. and how would one use it???


Infinite Radiant Light - THKRA
 
 
 
 
    terbium
(Old P2P Cook)
04-26-02 07:59
No 301530
      Raney  Bookmark   

Search on just the string  "raney" (without the quotation marks) and you will get hundreds of hits. I got 285, you should now get at least 286.
 
 
 
 
    zed
(Newbee)
04-26-02 10:56
No 301563
      Pressure vessels.  Bookmark   

The internal dimensions of a pressurized vessel, largely determine what materials it must be constructed of, and how thick its walls must be.

Small internal diameter, tubing can sustain incredibly high pressures. This is why: If the pressure is 1000 psi, but the actual internal surface area exposed to that pressure is is only 1/10 of a square inch per linear inch of tubing, the internal pressure on that 1/10 of a square inch is only 100lbs.

When designing a pressure vessel keep in mind, it is not say, 1000 lbs of pressure. It is 1000 lbs of pressure per square inch. The pressure actually exerted on a cap, or end plate having an an internally exposed surface of 25sq. inchs, is 25,000 lbs!

The physics of the matter indicates that such vessels should be tall and narrow.

Hydrotesting any self designed/constructed vessel is imperative. Pressure test it with water. Water being incompressable, if your vessel fails pressure testing, it will just go sploosh. If you test it with air or some other gas, and it fails at high pressure, grandma's barn may disappear and take you with it.

Which takes us to the next point. Since Raney/Nickel has been mentioned, I'm kind of assuming some want a pressure vessel for the "Gee Whiz", one step reduction of nitro-propenyl benzenes to phenyl-isopropylamines via Raney Nickel/H2. If you know someone who has succeeded at this reduction, and they can coach you, perhaps it is worth while.

An excellent buddy of mine, once had such a vessel, his actual yields were very non-satisfactory. He returned to other methods of reduction.

Raney/Nickel may not be poisoned by some materials that kill Pt/Pd catalysts. This is good. It also may accomplish some reductions that Pt/Pd will not. It is cheap which is good, but Pyrophoric which is bad. It usually requires lots of pressure and special equiptment, my opinion of which I have already stated.

If you plan to go that way, try to make sure it is going to work for you.

I wish you health and long life......................zed
 
 
 
 
    ClearLight
(Hive Bee)
04-26-02 11:32
No 301575
      re: pressure etc..  Bookmark   


  your right zed, that's why psi is appended to the measurements...smile

  The raney nickel came up as I have about 5 lbs of it laying around I picked up in a chem supplier "going out of business" sale... along with an amazing amount of other stuff... Most of the posts seemed to be oriented towards eph. reduction, and meth is not in my candy lineup...

  bee nice if it worked well for MDMA but doesn't seem so..

thx


Infinite Radiant Light - THKRA
 
 
 
 
    Cept
(Hive Bee)
03-31-03 14:45
No 422734
      Paintball Tanks as Reduction Vessels?  Bookmark   

Remember when our Hive Prodigy wrote...
"Try this one: Nitrogen propellant tanks for paintball guns.

They withstand up to 4000psi. The typical charge pressure is 3000psi. Don't give me any shit about units, that's what's on the tank. Just remember that one atmosphere is ~14psi, and that's all it takes for you to realize that thse will not burst at hydrogenation pressure: ~3 atmospheres.

They are epoxy-resin wrapped glass tanks, and have removable pressure valves at the top. The valves have built in pressure guages that go up to....you guessed it, 4000psi. They have a semirounded bottom, and since they are glass, I suspect that if I stirbar were introduced inside the unit, it would operate just fine.

Remove the cap, introduce your reactants, re-affix the valve and guage, attach the hydrogen tank, and "charge" the tank up to a mere 45psi from a hydrogen tank instead of nitrogen."

---------------------------------------------------------
    So what's the scoop? Has anyone tried this interesting method? For clarification though, are they glass tanks? or internally glass coated? it'd be so shady to think of a tank made of glass at high psi. PrimoPyro, have you had any dreams/nightmares with such silly conCepts? I was gonna private message you but i'm downloading too much right now.

I'm trying to download every one of yall's posts ever written!!! Its my new Obsessive task; although this damn internet program can't do it cuz of passwords and login errors. Its been a month of all-niters (spent neurons-no fun; what's that about learning mechs?). I'll do it one by one, by hand. He hesmile. Maybe i'll zip it and post it (too long, yup-yup)? or sleep with it.
 
Seems quite interesting to go unnoticed for so long...i dunno...
 
  Anyways, if nobody has tried this yet maybe Cept'l give it a little go. No promises. Tips welcome. Have a nice day.
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