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Can someone please explain why the carbonyl group in the below picture is a better electrophile?
Can someone please explain why the carbonyl group in the below picture is a better electrophile?
Thank you very much. Is it safe to say the carbonyl molecule is more polar then?It's because of the double bond. The oxygen "hogs" more of the electrons via the double bond, making the sp2 carbon more positive than the sp3 carbon.
Thank you very much. Is it safe to say the carbonyl molecule is more polar then?
No. C-OH is more polar than C=O
Your awesome. Thank you very much for the detailed response. May I ask why a double bond creates a stronger dipole than a single bond? I assume it is because sp2 is more electronegative than sp3? Is it safe to say a triple bond has a stronger dipole than a double and single bond?Nucleophilicity and electrophilicity are kinetic concepts - so you take into account both sterics and electronics. In terms of electronics, the C=O bond simply has a stronger dipole than the alcohol and thus is better at withdrawing electron density from the carbonyl carbon, making it more electrophilic. Sterically, the ketone is also more electrophilic because it's in a trigonal planar geometry, which creates less steric hindrance to nucleophile attack than a tetrahedral geometry. Also a side note - nucleophilic attack on an sp2-hybridized carbon is no longer an SN1/2 mechanism. SN1/2 are used in relation to sp3 carbons. The correct term is the more general "nucleophilic addition" or in certain cases depending on the nature of your carbonyl, a nucleophilic acyl substitution.
Hahaha^^ What he said lol.
Your awesome. Thank you very much for the detailed response. May I ask why a double bond creates a stronger dipole than a single bond? I assume it is because sp2 is more electronegative than sp3? Is it safe to say a triple bond has a stronger dipole than a double and single bond?
Your awesome. Thank you very much for the detailed response. May I ask why a double bond creates a stronger dipole than a single bond? I assume it is because sp2 is more electronegative than sp3? Is it safe to say a triple bond has a stronger dipole than a double and single bond?