Question

Write the product when 1°, 2° and 3° alcohol vapours are passed over hot copper.

Answer 1

1. Hot copper with 1° alcohol gives aldehyde.
   \[\ce{\underset{(1° alcohol)}{R - CH2 - OH} ->[Cu/573K][(O)] \underset{(Aldehyde)}{R - CHO}}\]
2. Hot copper with 2° alcohol gives ketone.
   \[\begin{array}{cc}\\
   \ce{R - CH - R' ->[Cu/573K][(O)] R - C - R'}\\
   \phantom{}|\phantom{.....................}||\phantom{.}\\
   \phantom{.}\ce{\underset{(2° alcohol)}{OH}\phantom{..............}\underset{(Ketone)}{O}}\phantom{..}
   \end{array}\]
3. Hot copper with 3° alcohol gives alkene.
   \[\begin{array}{cc}
   \ce{H3C - C(OH) - CH3 ->[Cu/573K][(O)] H3C - C = CH2}\\
   \phantom{}|\phantom{..............................}|\phantom{.}\\
   \phantom{.}\ce{\underset{(3° alcohol)}{CH3}\phantom{.......................}\underset{(Alkene)}{CH3}}\phantom{}
   \end{array}\]