Question

An organic compound (A) with molecular formula C₂Cl₃O₂H is obtained when (B) reacts with Red P and Cl₂. The organic compound (B) can be obtained on the reaction of methyl magnesium chloride with dry ice followed by acid hydrolysis.

a. Identify A and B

b. Write down the reaction for the formation of A from B. What is this reaction called?

c. Give any one method by which organic compound B can be prepared from its corresponding acid chloride.

d. Which will be the more acidic compound (A) or (B)? Why?

e. Write down the reaction to prepare methane from the compound (B).

Answer 1

a. (A): CCl₃COOH (B): CH₃COOH

b. \(CH_3COOH\xrightarrow[\text{(ii)}H_2O]{\text{(i) Red }P/ Cl_2} CCl_3COOH\), Hell Volhard Zelinsky reaction

c. \(CH_3COCl \xrightarrow{H_2O}CH_3COOH\)

d. A will be more acidic due to presence of 3 Cl groups (electron withdrawing groups) which increase acidity of carboxylic acid.

e. \(CH_3COOH \xrightarrow{\text{(i)NaOH, CaO (ii) heat}}CH_4 + Na_2CO_3\)