cueva (Stranger)
06-07-00 06:21
No 14683
      mechanism of isomerization  Bookmark   

how do isomerization reactions work? what's the mechanism? it bothers me to look at these reactionsa and accept dogmatically that they work without knowing HOW they work. the beauty of organic chemistry is the explanation of how reactions work, not the reactions themselves, right?

 
 
 
 
    Blaze2
(Stranger)
06-07-00 11:57
No 14807
      Re: mechanism of isomerization  Bookmark   

Is not the isomerisation of an allylbenzene to propenyl known as a prototropic rearrangment

 
 
 
 
    Rhodium
(Chief Bee)
06-07-00 13:17
No 14840
      Re: mechanism of isomerization  Bookmark   

What is a prototropic rearrangement? "proton rearrangement"?

http://rhodium.lycaeum.org
 
 
 
 
    CHEM_GUY
(Hive Bee)
06-07-00 23:57
No 15037
      Re: mechanism of isomerization  Bookmark   

Isomerization has several different mechanisms by which they work and therefore is to exhaustive of a subject to try to tackel without some direction to focus upon.  Some are basic thermodynamics, the formation of more stable compounds, other are a consequence of intermeidatary compound formation, and other yet can be surface catalyzed, and the list goes on...

What specific isomerization are you inquiring about? 

This post is for informational purposes only an is not intended to facilitate illegal activity.
 
 
 
 
    cueva
(Stranger)
06-08-00 19:24
No 15485
      Re: mechanism of isomerization  Bookmark   

proton rearangement? sounds easy.  the question is still unanswered, how does it work (what is the mechanism)? specifically, the reaction im talking about is just a change in the position of a double bond (aka proton rearangement), say, safrole to isosafrole with CaO and base. what does the CaO accomplish? the base?

 
 
 
 
    Rhodium
(Chief Bee)
06-08-00 23:02
No 15534
      Re: mechanism of isomerization  Bookmark   

The CaO absorbs the water present in the KOH, forming Ca(OH)2

http://rhodium.lycaeum.org
 
 
 
 
    Osmium
(Moderator)
06-09-00 13:16
No 15797
      Re: mechanism of isomerization  Bookmark   

The KOH probably removes the benzylic hydrogen, the double bond migrates and the H(+) reattaches itself onto the terminal carbon atom of that 3-carbon chain. Maybe some sort of chain reaction takes place too, meaning the hydrogen comes from the benzylic position of a second safrole molecule.