rearrangement reaction is a broad class of organic reactions where the carbon skeleton of a molecule is rearranged to give a structural isomer of the original molecule. Often a substituent moves from one atom to another atom in the same molecule, hence these reactions are usually intramolecular.

1. Presented by TANVI VYAS
M.SC (CHEMISTRY)
VON RICHTER REARRANGEMENT
&
SOMMELET-HAUSER
REARRANGEMENT

2. Von Richter Rearrangement :-
- The von Richter Rearrangement is a name reaction in the organic
chemistry.
- It is named after”Victor Von Richter”,who discovered this reaction.
- In this reaction ,when an aromatic nitro compound are reacted with
potassium cyanide (KCN) in aqueous ethanol to generate a corboxylic acid
Ortho to the existing nitro group is know as Victor Von Richter
Rearrangement.
It is the example of Cine substitution as ring substitution resulting in the
entering group to the precious location of the leaving group or we can say
that Ortho to the displaced group.

3. • As with other nucleophilic aromatic substitution , the reaction gives
better result when an electron withdrawing group are at Ortho and
para position.
• This reaction has limited applications in organic synthesis and yield of
the reaction is very poor.

5. Evidences of the reaction :-
• N2 is a major product of the reaction. This indicates that N-N bond
Must be formed during the course of the reaction.
• When the reaction was performed in H2
18O ,with CN ,half Oxygen in
the product was labelled showing that one of the oxygen of the
carboxylic group come from the nitro group and one from the solvent.
• When the reaction is carried out in the presence of D2O/C2H5OD,the
carboxylic acid formed contains deuterium at the position originally
occupied by the NO₂ group. This confirm the formation of species (B).

6. Sommelet-Hauser Rearrangement :-
• It is named after the M.Sommelet and R. Charles hause.
•It is a (2,3) sigmatropic rearrangement of benzylic quarternary
ammonium salt are treated with alkali-metal amides undergo a
rearrangement called Sommelet-hauser rearrangement.

7. Mechanism :-

8. Thank you!!