Mar 1, 2011
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The only explanation that would be to me .. is that the formal charges would be zero , however if they didn't share you will have +1 and -1 charge on carbons.
The alkene is the nucleophile because it is more electron dense and it is bonded to methyls that donate electrons to sp2 carbon, on other side the carbon with 2 Cl is electronegative but it is less elctronegative thus it serves as an electrophile because each Cl is electron withdrawing and they cause the carbon to become less electronegative thus serving as an electrophile.
Thats how i would understand it, however I really don't see these kinds of questions given without a passage, and in most times the passage will guide your thinking towards the best answer.
 
Jul 9, 2011
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It's just one of those stupid things....

But seriously, you won't have to know this.
You will have to know relative descriptions and qualities of electrophiles, but not electrophillic reactions like these.
 
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chiddler

5+ Year Member
Apr 6, 2010
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nvm.

forget this question.

thanks for your help guys.
 
Jul 9, 2011
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I was given that the carbene is a neutral molecule.

I don't understand what you mean though. The carbene is giving electrons to the alkene, and it is accepting electrons. It is reciprocal. Why is it accurate to label the carbene as an electrophile?
Oh I see.


Well in that case you can think of it as an H that is being ripped off via E2.
The H is a defined electrophile.

1.) nucleophile's electrons hit the H

2.) The H gives it's bonding electrons down to the attached carbon, to create a double bond.

Even though the H ends up giving electrons out, it's still considered an electrophile.



Now I know that this isn't exactly an ideally comparable case because the H is bonded and not freely "throwing it's electrons" but it is a concept of, what gets hit first is the electrophile.