Carboxylic Acid Derivatives – Part 2 | Organic Chemistry 3

Additional reactions of carboxylic acid derivatives are studied in this chapter: Hofmann rearrangement, name and properties of alkanenitriles, hydrolysis of nitriles, reactions between nitriles and organometallic reagents, reduction of nitriles

Hofmann Rearrangement


Mechanism:

  1. Amidate formation:


     
  2. Halogenation:


     
  3. N-haloamidate formation:


     
  4. Rearrangement with halide elimination:


     
  5. Carbamic acid hydration and decomposition:

Alkanenitriles: Nomenclature and Properties

Nomenclature:

The ​​​-ic acid ending of the corresponding carboxylic acid is replaced with -nitrile. The substituent -CN is called cyano. A cycloalkane with a cyano group attached to the ring is called cycloalkanecarbonitriles
Nitrile takes precedence over aldehyde, ketone, amine, alkene, alkyne

 

 

Properties:

- sp hybridization ⇒ linear geometry
- IR: stretching vibration ~ 2250 cm-1
- NMR: 13C δ ~ 120 ppm

Hydrolysis of Nitriles


Mechanisms:

Acid-catalyzed hydrolysis:
 

 

Base-catalyzed hydrolysis:
 

Nitriles and Organometallic reagents

Reduction of Nitriles