What is steric shielding

MinisterOfSillyWalks



Registration date: 02/23/2006
Posts: 178
Place of residence: was once Karlsruhe (& TH)
Posted: Jun 06, 2006 7:50 PM Subject:

Hello "Ronya",

To add to Cyrion's answer: on a carbonyl group, the carbon is positively polarized because the oxygen has a greater electronegativity and draws negative charges more towards itself.

One type of reaction that likes to take place on such a positively polarized carbonyl carbon is nucleophilic addition (A.N), in which an electron-rich substituent wants to attach itself to this positivized carbonyl carbon, if, yes if, not too large neighboring groups to the right and left of the carbonyl carbon sterically (i.e. spatially) impede this approach.
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