Resonance electron-withdrawing group

Substituents such as NOz, C=N, S02CH3, CONH2, and COOR can donate an electron pair to reaction centers such as OH, NH2, OR, and SH. In the presence of a strong-resonance electron-withdrawing group and a strong-... 

Resonance effects Resonance electron-withdrawing groups make the carbonyl carbon more electrophilic and increase the rate resonance electron donors make the carbonyl carbon less electrophilic and decrease the reaction rate. 

Memorization Task 19.6 Identifying Resonance Electron-withdrawing Groups... 

A group with a % bond next to an aromatic ring will be a resonance electron-withdrawing group... 

No ordinary EAS reactions work with very deactivated rings. As a mle of thumb, a ring is considered very deactivated if it has two resonance electron-withdrawing groups (and no resonance electron-donating groups to counterbalance this). 

Put a box around each resonance electron-withdrawing group on the starting materials in Model 5. 

Explain why NAS works well with one or more resonance electron-withdrawing groups ortho or para to the leaving group, but not when such a group is meta. 

Construct an explanation for why neither of the aromatic rings at right will undergo NAS even though each has two resonance electron-withdrawing groups. 

NMR is a valuable tool for evaluating the electron withdrawing effect of aryl substituents in potential monomers. When a resonance electron withdrawing group is present on a... 

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