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Chemistry Forums for Students => Inorganic Chemistry Forum => Topic started by: KritikalMass on April 02, 2010, 07:13:03 PM

Title: How do the carbons in carborane have six bonds?
Post by: KritikalMass on April 02, 2010, 07:13:03 PM
Could someone please give me some hints or direct me to some literature that explains how it is that the carbons in carborane can have six bonds? All throughout organic chemistry they kept emphasizing how carbon can never have more than four covalent bonds, but here in carborane the carbons have six bonds. My only hypothesis is that the bonds are not entirely covalent. When I asked my polymer chemistry professor he said that thinking about carborane gave him a headache and he advised me to try to figure it out on my own. Thanks!
Title: Re: How do the carbons in carborane have six bonds?
Post by: Jorriss on April 02, 2010, 09:25:42 PM
Could someone please give me some hints or direct me to some literature that explains how it is that the carbons in carborane can have six bonds? All throughout organic chemistry they kept emphasizing how carbon can never have more than four covalent bonds, but here in carborane the carbons have six bonds. My only hypothesis is that the bonds are not entirely covalent. When I asked my polymer chemistry professor he said that thinking about carborane gave him a headache and he advised me to try to figure it out on my own. Thanks!
So, I've only taken general chemistry so I don't really know. But could it be half bonds, like the case is with B2H6?

Take a look at this,
http://en.wikipedia.org/wiki/Three-center_two-electron_bond
Title: Re: How do the carbons in carborane have six bonds?
Post by: KritikalMass on April 02, 2010, 10:14:41 PM
So, I've only taken general chemistry so I don't really know. But could it be half bonds, like the case is with B2H6?

That's so funny that you mentioned that because he did kind of try to explain it and that was the exact same molecule he used as an example. He said the boron is "sp3 distorted". He then said that maybe the carbons are doing something similar. I appreciate you're answer, and will definitely check it out, although I do believe that there is a more precise answer.

Thanks for your response  :)
Title: Re: How do the carbons in carborane have six bonds?
Post by: stognerb on April 02, 2010, 10:44:39 PM
I am not sure at all but the first thing that would come to mind for me is that it was derived from carbenes
Title: Re: How do the carbons in carborane have six bonds?
Post by: KritikalMass on April 03, 2010, 11:43:36 AM
So, I've only taken general chemistry so I don't really know. But could it be half bonds, like the case is with B2H6?
Take a look at this,
http://en.wikipedia.org/wiki/Three-center_two-electron_bond

Yes, that is what it was.

http://www.princeton.edu/~mjjr/1,2-de.html

Thank you.