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edited Mar 11, 2018 at 2:03

Gaurang Tandon

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I've got two set of reactants -

i) 4-nitrobromobenzene + Sodium methoxide:

ii) Sodium 4-nitrophenoxide + bromomethane

4-nitrobromobenzene + sodium methoxide

sodium 4-nitrophenoxide + bromomethane

I've got to tell which reaction is more preferable among these two .

The first reaction takes place through Nucleophilicnucleophilic addition of methoxide on the ring followed by elimination of Brominebromine. I've been taught that such reactions take place under drastic conditions , but the presence of an electron withdrawing group at ortho and para position increases the reactivity, so the presence of NO2$\ce{NO2}$ group should increase the reactivity . The

The second reaction takes place by SN2S_N2 mechanism , where bromomethane is attacked by the nitrophenoxide ion . This reaction "seems" to be better than the first. (Is it?)

MyHence, my attempt is that the second reaction should be more favourable than the first since the first reaction should take place under more drastic conditions than the second.

My question is- Am iAm I right? Or Or does the presence of NO2$\ce{NO2}$ group increase the reactivity so much that it is comparable to the second reaction or maybe better?

I've got two set of reactants -

i) 4-nitrobromobenzene + Sodium methoxide

ii) Sodium 4-nitrophenoxide + bromomethane

I've got to tell which reaction is more preferable among these two .

The first reaction takes place through Nucleophilic addition of methoxide on the ring followed by elimination of Bromine. I've been taught that such reactions take place under drastic conditions , but the presence of electron withdrawing group at ortho and para position increases the reactivity, so the presence of NO2 group should increase the reactivity . The second reaction takes place by SN2 mechanism , where bromomethane is attacked by nitrophenoxide ion . This reaction "seems" to be better than the first. (Is it?)

My attempt is that the second reaction should be more favourable than the first since the first reaction should take place under more drastic conditions than the second.

My question is- Am i right? Or does the presence of NO2 group increase the reactivity so much that it is comparable to the second reaction or maybe better?

I've got two set of reactants:

4-nitrobromobenzene + sodium methoxide

sodium 4-nitrophenoxide + bromomethane

I've got to tell which reaction is more preferable among these two.

The first reaction takes place through nucleophilic addition of methoxide on the ring followed by elimination of bromine. I've been taught that such reactions take place under drastic conditions, but the presence of an electron withdrawing group at ortho and para position increases the reactivity, so the presence of $\ce{NO2}$ group should increase the reactivity .

The second reaction takes place by S_N2 mechanism, where bromomethane is attacked by the nitrophenoxide ion. This reaction "seems" to be better than the first. (Is it?)

Hence, my attempt is that the second reaction should be more favourable than the first since the first reaction should take place under more drastic conditions than the second.

Am I right? Or does the presence of $\ce{NO2}$ group increase the reactivity so much that it is comparable to the second reaction or maybe better?

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asked Mar 10, 2018 at 18:45

Utkarsh

Which set of reactants is better for preparation of 1-methoxy-4-nitrobenzene?

I've got two set of reactants -

i) 4-nitrobromobenzene + Sodium methoxide

ii) Sodium 4-nitrophenoxide + bromomethane

I've got to tell which reaction is more preferable among these two .

My attempt is that the second reaction should be more favourable than the first since the first reaction should take place under more drastic conditions than the second.

My question is- Am i right? Or does the presence of NO2 group increase the reactivity so much that it is comparable to the second reaction or maybe better?

organic-chemistry