Main Index   Search   Register   Login   Who's Online   FAQ   Links
  1 Online, 0 Active   You are not logged in  
Main Index     The HIVE light edition (TM)
This is a historical archive
The forum is read-only. Private information has been removed. It is not possible to login.


Chemistry Discourse Thread:   Previous  Forum index  Next

All 10 posts   Subject: enolate formation from calcium carbide?   Please login to post   Down

 
    stratosphere
(Hive Bee)
12-10-03 20:46
No 475993
      enolate formation from calcium carbide?     

calcium carbide is a very strong base (not quite MeLi, but lots stronger than hydroxide) that also happens to be readily available in bulk...

it would seem reacting it with acetone would drive off acytelene (indeed just going by pka's the pka of acytelene is 25 and that of acetone is 19, so its plenty strong to deprotanate acetone) and yield the enolate of acetone, which should do fun stuff with phenylhalides...

so if it were really this easy, why have i not found anything in tfse about this method?
 
 
 
 
    java
(Hive Bee)
12-10-03 22:18
No 475999
      RE: Enolate acetone.....     

Just recently Ning had some coverage on the enolate process and there were many references and posts associated with it , which you might try to check out.....java

Post 455083 (ning: "Questions about drone's enolate p2p synth", Newbee Forum)

Note: Potassium tert-Butoxide  is another material available to enolate acetone.....so the literature says.

We're  all in this world together,
http://www.aztlan.net
 
 
 
 
    stratosphere
(Hive Bee)
12-11-03 22:12
No 476243
      i suppose if using calcium carbide directly to     

i suppose if using calcium carbide directly to produce acetone enol was unacceptable for some reason,
the CaC2 could be reacted with t-butanol to form calcium butoxide, this reaction would almost certainly be quicker and simpler then antochos otc alkoxide synth.
with CaC2 only costing ~$10(us)/lbs it would certainly seem a worthwhile thing to experiment with.
 
 
 
 
    java
(Hive Bee)
12-11-03 23:30
No 476248
      RE: Enolate acetone.....     

stratosphere......I think your theory could work but as to the solvent to use since it states in the process to use ammonia, since I don't know what it's function is, I imagine an excess of calcium butoxide , since it will keep the enol active to react with say Halobenzene to produce ......

ArX  +   CH3COCH3*  ---------> ArCH2COCH3 + ArCH2CHOHCH3
* acetone enolate

this of course would be great since acetone and CaC2 and the material to make the Halobenzene are pretty much OTC this would be one step closer to an easy method for P2P synthesis.......java

We're  all in this world together,
http://www.aztlan.net
 
 
 
 
    stratosphere
(Hive Bee)
12-12-03 00:33
No 476257
      i could not find any direct information on the     

i could not find any direct information on the reaction of CaC2 with alcohols, but i did see alchol as well as water listed as incompatiple with it, which would seem to indicate that indeed the alkoxide and acytelene do form, also from the pKa value it is evident that CaC2 is a stronger base then t-butyoxide.

i think for the solvent an excess of acetone would be used.

what is t-butanol sold otc for?
 
 
 
 
    algebra
(Hive Bee)
12-12-03 03:51
No 476295
User Picture 
      ammonia     

you dont need ammonia!! - use dmso - read the refs drone posted.
 
 
 
 
    java
(Hive Bee)
12-12-03 03:52
No 476297
      RE: Enolate acetone.....     

I would say about $80 dol/gallon.....not a bad investment to work on a dream that may have some honey of a result.......java

We're  all in this world together,
http://www.aztlan.net
 
 
 
 
    acx01b
(Hive Bee)
11-12-04 23:23
No 541296
User Picture 
      what to say about CaC2 ?     

what to say about CaC2 ?
i bougth some in france 10Euros 800grams, looks good quality (more than 90% purity) but not 99% (weird things not dissolving in water after reaction with water)

it is a strong base? why it doesn't work to dry some diethylether then ?
(is it new to you that CaC2 doesn't work to dry ether?)

enfin: CaC2 doesnt appear to react with acetone at all
 
 
 
 
    stratosphere
(Hive Bee)
11-14-04 12:55
No 541509
      the C2(-2) anion is a very strong base (i...     

the C2(-2) anion is a very strong base (i think i listed the pKb above).

thanks for the experimental results.
why it isn't working to dry ether or react with acetone, i can only speculate that it is reacting, but at a rate to slow for practical purposes, probobly due its crystal structure being to "tight".
my guess is that it would work well with Na2C2 but the problem of converting CaC2 to Na2C2 doesn't seem easily overcome.
 
 
 
 
    acx01b
(Hive Bee)
11-14-04 17:05
No 541524
User Picture 
      i thought melt some NaOH (0.5gram) and add...     

i thought about to melt some NaOH (0.5gram) and add some ~~powdered CaC2 in it, but because of the N2 present NaCN2 would be obtained probably (and Ca(OH)2) but maybe Na2C2 would be obtained in correct yield too

2nd thing: CaC2 reacts with ethanol but quite slowly: reaction is not complete at room temp...

refluxing is needed to get Ca-diethanolate and then Na-ethanolate, but even with refluxing i dont know how many time it takes, maybe 10hours to complete a 50grams scale reaction

i cant do refluxing anymore but boiling the ethanol makes the reaction faster, so i guess refluxing for 30min could work
 
 

All 10 posts   End of thread   Top
   

 https://the-hive.archive.erowid.org    the-hive@erowid.org
   
Powdered by Strapadictomy(R) Version 6.7, 2023, THC-Soft

Links     Erowid     Rhodium

PIHKAL     TIHKAL     Total Synthesis II

Date: 07-16-24, Release: 1.6 (10-04-15), Links: static, unique