(i) What is Clemmensen reduction? Explain it.
(ii) Write the structure of the major product of the aldol condensation of benzaldehyde with acetone.

Explanation

(i) Aldehyde and ketones when heated with zinc amalgam and concentrated hydrochloric acid give hydrocarbons. This reaction is known as Clemmensen reduction.
`underset("Acetaldehyde")(CH_(3)-underset(O)underset(||)C-H+4[H]) underset("Conc HCl")overset(Zn+Hg) to underset("Ethane")(CH_(3)-CH_(3)+H_(2)O)`
(ii) Aldol condensation of benzaldehyde with acetone:
Step 1:


Step 4:
`C_(6)H_(5)-underset(OH)underset(|)(CH)-CH_(2)_COCH_(3) underset(-H_(2)O) overset(Delta)to underset(("Benzylidene acetone"))(C_(6)H_(5)-CH=CH-COCH_(3))`