(a) Describe the following actions :
(i) Acetylation
(ii) Aldol condensation
(b) Write the main proudction in the following equations : (i) `CH_3-underset(O)underset(||)C-CH_3overset(LiA//H_4)to`?
(ii)
(iii) `CH_3-COOHoverset (PCl_5)to` ?

Explanation

(i) Acetylation : The replacement of an active hydrogen of alcohols, phenols or amines with an acyl (RCO) group to form the corresponding amides is called acetylation. This replacement is carried out by using acid chloride or an acid anhydride in the presence of a base like pyridine or dimethylaniline.
`CH_3COCl+C_2H_5OH overset ("Pyridine")tounderset("Ethyl acetate")(CH_3COOC_2H_5+HCI`
(ii) See Q.30 ,(or) D.B.Set -I, 2012.

(b) (i) `CH_3-underset(O)underset(||) C-CH_3 overset(LiA//H_4)to -underset("Propane")CH_2-CH_3`
(ii)
(iii) `underset("Acetic Acid")(CH_3COOH)overset(PCl_5)toundersetunderset(alpha"-chloro-acetic acid")(Cl)underset(|)CH_2-COOH`