Chelating Complexes

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Ai-nhi Tran 3A
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Chelating Complexes

Postby Ai-nhi Tran 3A » Sat Nov 07, 2015 5:24 pm

What is the exact definition of a chelating complex?
And how do you determine whether or not an isomer can form a chelating complex?

Chem_Mod
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Re: Chelating Complexes

Postby Chem_Mod » Sun Nov 08, 2015 2:57 am

A ligand is capable of chelating a metal if it has many binding sites, for example, if it is hexadentate.

Typical examples of cheating ligands are EDTA and crown ethers.

Samantha Rundle 3K
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Re: Chelating Complexes

Postby Samantha Rundle 3K » Sun Nov 08, 2015 6:21 pm

I understand the definition of a chelating complex, but how would one go about identifying whether or not a molecule can form a chelating complex by looking at lewis structures like in problem 17.35 in the homework?

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Re: Chelating Complexes

Postby Chem_Mod » Sun Nov 08, 2015 8:50 pm

What does the problem state?

Jacob Afable 3J
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Re: Chelating Complexes

Postby Jacob Afable 3J » Wed Nov 11, 2015 11:15 am

Chem_Mod wrote:What does the problem state?
Attachments
Screen Shot 2015-11-11 at 11.14.10 AM.png

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Re: Chelating Complexes

Postby Chem_Mod » Wed Nov 11, 2015 1:45 pm

Notice the b) looks like ethylenediamine if you just consider the part that goes N-C-C-N. So it will be able to bind two sites, and with 3 of these ligands you could chelate the molecule.

On the other hand, in a) the nitrogen are too far away: you cannot bind two sites on a metal with groups that are 180-degrees apart. Similarly, in c) although the nitrogen are closer, they are still not in the correct relative position to bind multiple sites, since the benzene ring is rigid.


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