There is a similiar question posted here http://www.chegg.com/homework-help/ques

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There is a similiar question posted here

http://www.chegg.com/homework-help/questions-and-answers/substituents-aromatic-ring-several-effects-electrophilic-aromatic-substitution-reactions-s-q4423056

But I am still not sure based on the different groups provided in my question

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3/20/2016 11:55 PM A 19/20 Gradebook Calculator Periodic Table Question 3 of 20 Mapoob sapling learning Substituents on an aromatic ring can have several effects on electrophilic aromatic substitution reactions Substituents can activate or deactivate the ring to substitution, donate or withdraw electrons inductivel donate or withdraw electrons through resonance, and direct substitution either to the ortho/para or to meta positions. From the following lists, select the substituents that have the indicated property. The substituents are written as-XY X is the atom directly bound to the aromatic ring Activation of the ring towards substitution Withdrawal of electrons through resonance Ortho/para-directed substitution -C -COOH -NHCOCH 3 OCOCH3 -OCH3 -CI -NO2 -OH NHCOCH3 -CH3 Previous Give Up & View Solution O Check Answer Next Exit

Explanation / Answer

1) Activation of the ring towards substitution: for this, we want to find the substituents of the form -AB where A is more electronegative than B (in other words, the atom that is directly bonded to the benzene ring must have a higher electronegativity).

Answer: -OCOCH3 and -NHCOCH3 fall in this category.

Additional explanation: O has a higher electronegativity than C as N has a higher electronegativity than H.

2) Withdrawal of electrons through resonance: as a general rule; halogens, functional groups with a carbonyl group (aldehydes, ketones, esters, carboxylic acids...), CN- and NO2- fall in this category. These substituents deactivate the ring and are meta directors (except haloges which are ortho and para directors).

Answer: -COOH and -CN fall in this category.

3) Ortho/para directed substitution: the same rule as 1) applies (we want to find the substituents of the form -AB where A is more electronegative than B), but halogens are also included here.

Answer: -NHCOCH3, -Cl and -CH3 fall in this category.

Additional explanation: N has a higher electronegativity than H as C has a higher electronegativity than H. Cl is a halogen that deactivates the ring but still directs towards ortho/para positions.

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