Question

(b) What happens when methanol is heated with HI in presence of red phosphorus?
(c) State and explain Gattermann reaction.

Answer 1

Answer:

1} When ethanol is heated with red phosphorous and hydrogen iodide, It produces CH3CH2I. The organic product formed when ethanol is heated with red phosphorus and hydrogen iodide is ethyl iodide. Here red phosphorous is used as a catalyst.

red phosphorous is used as catalyst to activate reaction. in hell volard zelinsky reaction , red phosphorous will react vigrously with bromine to give phosphorous tribromide . so, red phosphorous is used as a reagent here , and also it will initiate the reaction .

2}The Gattermann-Koch Reaction involves the formation of an aryl aldehyde using carbon monoxide and hydrochloric acid as reactants. The reaction is catalyzed by aluminium trichloride in the presence of trace amounts of cuprous chloride.

Reaction of a phenol or phenol ester, and hydrogen chloride or hydrogen cyanide, in the presence of a metallic chloride such as aluminum chloride to form, after hydrolysis, an aldehyde.

Reaction of an aqueous ethanolic solution of diazonium salts with precipitated copper powder or other reducing agent to form diaryl compounds.