Why in Nucleophilic addition-elimination reactions,does the #C=O# bond break when the nucleophile is added and not the#C-CL# bond ?

1 Answer
anor277
Nov 21, 2016

I take it you refer to nucleophilic attack on an #"acyl halide"#?

Explanation:

#"Reaction: " Nu^(-) + Cl(O=)CRrarr(Nu)(""^(-)O)(Cl)CRrarr Nu(O=)CR +Cl^-#

The carbonyl is presumed to stabilize the negative charge of the nucleophile, presumably by resonance. The ipso carbon is thus 4-coordinate, and we could trap such an intermediate by quenching with, say, #Me_3SiCl# to give #(Nu)(Me_3SiO)(Cl)CR#.

Does this address your query?

Related questions
See all questions in Nucleophile vs. Base Strength
Impact of this question
2007 views around the world
You can reuse this answer
Creative Commons License