Question

Write one chemical equation to illustration of the following
A. Etard reaction
B. Wolff kishner reduction
C. Gattermann-koch reaction

Answer 1

IWe are given the three reactions. Etard reaction, Wolff kishner reduction, Gattermann-koch reaction. We will look into each one by one. Etard reaction is a reaction which offers a method to oxidize aromatic methyl groups, Wolf-Kishner is the reduction reaction and Gatterman-Koch reaction is often used for industrial production of the benzaldehyde.

Complete step by step answer:
Step1. Etard reaction is a reaction which offers a method to oxidize aromatic methyl groups . It is oxidation of aromatic methyl groups to the aldehydes using chromyl chloride. If we see the example it can be that the toluene is oxidized to benzaldehyde using the etard reaction. The reaction begins with the alkene or allylic hydrogen reaction with chromyl chloride, forming a precipitate called Etard complex.
Equation of etard reaction:
${C_6}{H_5}C{H_3}\xrightarrow{{Cr{O_2}C{l_2} + C{S_2}}}{C_6}{H_5}CH{\left( {OCrOHC{l_2}} \right)_{2\xrightarrow[{ - HCl}]{{ - CrClOH}}}}{C_6}{H_5}CHO$
Step2. Wolf-Kishner is the reduction reaction in organic chemistry. It converts carbonyl functions into the methylene groups. At first the reduction starts when the hydrazine anion which releases the nitrogen atom to form a carbanion. This ion reacts with the water in the system to give hydrocarbon. Often diethylene glycol is used as a solvent.
Equation of Wolf-kishner reaction:
$C{H_3}COC{H_3}\xrightarrow{{N{H_2}N{H_2}}}C{H_3}C{H_2}C{H_3} + {N_2}$
Step3. Gatterman-Koch reaction is often used for industrial production of benzaldehyde. In this benzene is treated with carbon monoxide when the anhydrous aluminium chloride is present in the acidic medium to give benzaldehyde. This reaction is an electrophile reaction. The aldehyde group is attached to aromatic ring by Gatterman-Koch reaction
Equation of gattermann Koch reaction :
${C_6}{H_6}\xrightarrow[{AlC{l_3} + HCl}]{{CO}}{C_6}{H_5}CHO$

Note: An electrophilic addition reaction is an addition reaction. In this reaction a pi bond reaction and then two sigma bonds are formed. In a reaction the major product is decided by the stability of the carbocation and carbanion.