How can I quickly recognize a nucleophile or electrophile?

[jp313]

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How do you quickly recognize a nucleophile and electrophile molecule without seeing the positive and negative charge?

 

[UBCStudent128]

How do you quickly recognize a nucleophile and electrophile molecule without seeing the positive and negative charge?

You can think of electrophile = lewis acid nucleophile = lewis base
Nucleophiles have a free lone pair electron to attack the electrophile.

Or you can see which molecule has a good leaving group. Electrophiles have leaving group 🙂

Once you do enough problems, you can usually identify nucleophiles right away since they reuse a lot of the typical nucleophiles like Tert BuOK, MeOH, etc

 

[invictusx]

Nucleophile = something that loves going to the nucleus
Electrophile = something that loves going to an electron deficient carbon (+ charge)

 

[whodat4life]

Electrophile - will most likely have a positive charge
Nucleophile - will most likely have a negative charge

I'm sure there are rare exceptions, but that's the rule I always went by and did well with it. Good luck!

 

[winnie bear]

How do you quickly recognize a nucleophile and electrophile molecule without seeing the positive and negative charge?

For nucleophiles, look for a negative charge or lone pairs that can attack. Write it like this :Nu-. Negative attacks positive. :Nu- -------> E+

For electrophiles, look for a positive charge or electron deficiency or partial positive. Write it like this E+. Positive is attacked by the negative E+ <--------:Nu-

Another way to remember is that nucleophiles are so negative and can't stand looking at positives be happy so it attacks anything that's positive b/c misery loves company. Kay, that was kinda dumb, but it helps to form association to help recall if the two really confuse you😳).

 

[UBCStudent128]

lol didn't the OP say WITHOUT having charges?
Why are all these answers having to do with charges.

If it has a free lonepair, it is most likely nucleophile.
If it does not have a lonepair, it can not be a nucleophile. It has to be an electrophile