Friday, September 7, 2012

Conformation vs. configuration


Before I start posting on the different types of isomers, I will devote a post to an aspect that is very important when studying the isomerism of molecules. Despite its great importance, this can be sometimes confusing ... I'm talking about the difference between conformation and configuration. J
These two concepts are often used interchangeably, but represent very different things. The conformation regards the relative spatial orientation of a portion of a molecule relative to another. Thus, it is an aspect that is not directly related to the covalent bonds that are established within the molecule, but with their possible rotation.



When we talk about rotation around covalent bonds, we are only referring to the single bonds, as they are the only ones that can suffer rotation. Basically this concept is easily understood if we think that the bounds work as an axis...


It should be noted that when we speak of different conformations, it does not necessarily involve all the covalent bonds of a molecule, it can account only for one or few of them.




Taken together, it is possible to convert one conformation to another without cleaving or forming chemical bonds, simply by rotating some simple covalent bonds.

The configuration is a concept that is related to the order by which different substituents linked to the same central atom establish covalent bonds. That means, in this case it is clearly an aspect that is a direct consequence of the covalent backbone of molecules.


To change the configuration, you must always cleave and form new covalent bonds...

 
In conclusion, the concept conformation encompasses portions of a molecule which are not directly linked to the same atom and do not involve the covalent backbone of the molecules, while the configuration comprehends parts of the molecule which are bound to the same atom, which means that there is a direct involvement of the covalent bounds of the molecule.

24 comments:

  1. Thank you! This is the clearest explanation of the differences between conformation and configuration I've read. One thing that might make a nice addition is showing a mechanism where the addition/destruction of a covalent bond changes the configuration.

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    1. Hi lisa,

      thank you very much for your message, I am glad you enjoyed my post. Also thank you for your suggestion, for sure I will include it in a future post! :)

      Delete
  2. Why is there random wingings font in the beginning of the post?

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    1. Sorry but I cannot see the random wingings. Can you please send me a print screen of what you see?

      Thank you. :)

      Delete
  3. thank you! that was cristal clear!
    George

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    1. Hi George,

      thank you for your visit, I am glad to hear that you liked the post! :)

      Delete
  4. Replies
    1. Hi Lycan Wolves,

      I am happy to hear that you enjoyed the post.

      Thank you for your visit! :)

      Delete
  5. I agree with Lisa. Clearest explanation i read so far! Thank you very much:)

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    Replies
    1. Thank you for your kind comment, I am happy to know you found the post useful. :)

      Delete
  6. What about cis and trans stereoisomers? Are they considered to be different conformations or different configurations?

    Thanks!

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    1. cis and trans stereoisomers have different configurations (not conformations), and they belong to the family of geometric isomers. Please check the following post where I write about that kind of isomers:
      http://worldofbiochemistry.blogspot.pt/2012/11/geometric-isomers.html

      Thank you for your visit! :)

      Delete
  7. can we say confiramations are due to rotation of covalent bonds in three dimentional space but configurations are due to breakage and formation of covalent bond not necessarily in three dimention?????

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  8. can we say confiramations are due to rotation of covalent bonds in three dimentional space but configurations are due to breakage and formation of covalent bond not necessarily in three dimention?????

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    1. Hi,

      yes, that's correct. 3D structure refers to conformation, while formation and cleavage of covalent bonds refers to configuration.

      Delete
  9. Replies
    1. Hi,


      thank you for your kind comment and for the visit! :)

      Delete
  10. I am grateful to see the clear answer.. i really understand now what is the basic difference both of this.. and this question are very important for our Calcutta university also.. 😊

    ReplyDelete
    Replies
    1. Hi Jui,


      thank you for your kind comment and for the visit! :)

      Delete
  11. I am grateful to see the clear answer.. i really understand now what is the basic difference both of this.. and this question are very important for our Calcutta university also.. 😊

    ReplyDelete
  12. do conformation and configuration have similarities

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    1. Hi,

      yes, they have. They both represent different structures that a molecule can adopt, that means, ismeric forms.

      Than you for the visit! :)

      Delete
  13. Thank you for the abridged explanation in an easy to understand language.

    ReplyDelete
    Replies
    1. Hi,


      thank you for your kind comment and for the visit! :)

      Delete