Paid ADA sample DAT # 71

[tokyoman]

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p-bromonitrobenzene reacts 1. Sn,HCl ,2. NaNO2 , HCl (HONO), 3. CuCN

yields..

Ans. p-bromocyanobenzene ..

I can't draw the structures,, sorry. basically those reagent replaced NO2 group in bromobenzene to CN group..

whats going on with each reagent?

isn't Sn.HCl reducing agent that makes NO2 to NH2 ? I cant figure out what other ones does..

please help me someone

 

[UndergradGuy7]

1. Sn, HCl makes NO2 to NH2.
2. NaNO2 makes NH2 to N2.
3. CuCN replaces N2 with CN.

Step 3 can be replaced with other reactants like CuCl (to add Cl), KI (to add I), H3PO4 (to add H), H2O and heat (to add OH), etc. Basically the N2 can be replaced with H, Cl, I, etc.

Read organic chemistry chapter on Aryl Diazonium Ions.

Here is a summary
http://highered.mcgraw-hill.com/sites/dl/free/0072424583/35353/carey_5e_ch22_summary.pdf
Just look at the tables.

 

[tokyoman]

1. Sn, HCl makes NO2 to NH2.
2. NaNO2 makes NH2 to N2.
3. CuCN replaces N2 with CN.

Step 3 can be replaced with other reactants like CuCl (to add Cl), KI (to add I), H3PO4 (to add H), H2O and heat (to add OH), etc. Basically the N2 can be replaced with H, Cl, I, etc.

Read organic chemistry chapter on Aryl Diazonium Ions.

Here is a summary
http://highered.mcgraw-hill.com/sites/dl/free/0072424583/35353/carey_5e_ch22_summary.pdf
Just look at the tables.

wow How nice =) I kept looking for this in reactiong of benzene section.. so it is actually the amine!!

Thanks so much =) you are always so woderful