How do you convert NO2 to NH2?
It is necessary to use 3.5 moles of Na2S2O4 for 1 mole of substrate and boil for 1-1.5 hours in a mixture of ethanol-water (4:1). And then acidify with conc. HCl and boil for additional 5-10 minutes. The best method for reduction of NO2 to NH2 is to use H2 /Pt in acetic acid.
What reagent turns NO2 to NH2?
The best reducing agent to convert NO2 group to NH2 group is SnCl2 .
Is NO2 to NH2 reduction?
Nitration/Reduction provides an effective way to introduce an NH2 group. Reduction converts m- directing NO2 group into an o/p-directing NH2 group.
Does NO2 deactivate benzene ring?
Since NO2 is an electron withdrawing group, a glance at the resonance structures shows that the positive charge becomes concentrated at the ortho-para positions. Thus these positions are deactivated towards electrophilic aromatic substitution.
How do you convert nitro to amine?
Aliphatic nitro compounds can be reduced to aliphatic amines by several reagents:
- Catalytic hydrogenation using platinum(IV) oxide (PtO2) or Raney nickel.
- Iron metal in refluxing acetic acid.
- Samarium diiodide.
- Raney nickel, platinum on carbon, or zinc dust and formic acid or ammonium formate.
How do you convert CN to NH2?
- The nitrile, RC≡N, is reduced to the 1o amine by conversion of the C≡N to R-CH2-NH2
- Reagents : either lithium aluminum hydride (LiAlH4) / ether solvent or catalytic hydrogenation (e.g. H2/Pd).
- Alkyl nitriles are prepared by nucleophilic substitution (SN2) by cyanide ion, CN-, of primary or secondary alkyl halides.
How is NH2 removed from amine?
Reductive deamination (hydrodeamination) of aromatic amines can be conveniently carried out by amination of the corresponding arylamine methanesulfonamides using chloroamine under alkaline conditions. May be diazotization will help you out to remove -NH2 group.
How do you remove NH2 from benzene?
It is done at a temperature of less than 5∘C to form a stable compound by resonance. In deamination, nitrogen is removed by heating diazonium salt reacts with cold aq. Hypo phosphorous acid to evolve nitrogen and form benzene. This is how nitro groups are removed from benzene.
Why is NH2 more activated than NR2?
NR2 is more activating than NH2, this is because although NH2 is activating, the hydrogen atoms attached to nitrogen are -I groups and hence slightly reduce the activating ability. When the Hydrogen atoms were replaced by alkyl groups, alkyl groups being +I groups, increase the activating ability.
What happens when nitrobenzene reacts with LiAlH4?
Nitrobenzene on reduction with lithium aluminium hydride (LiAlH4) gives azobenzene.