Question

Which of the following Grignard reagents, is used to prepare 2-methylpentan-2-ol from acetone?

पर्याय

• \[\ce{CH3 - CH2 - Mg - I}\]

• \[\begin{array}{cc}
  \ce{CH3 - CH - Mg - I}\\
  |\phantom{.....}\\
  \ce{CH3}\phantom{..}
  \end{array}\]

• \[\ce{CH3 - CH2 - CH2 - Mg - I}\]

• \[\ce{CH3 - Mg - I}\]

Answer 1

\[\ce{CH3 - CH2 - CH2 - Mg - I}\]

Explanation:

\[\begin{array}{cc}
\phantom{.............................................................}\ce{OMGI}\phantom{.............................}\ce{OH}\phantom{...........................}\ce{I}\\
\phantom{............................................................}|\phantom{...................................}|\phantom{...........................}/\\
\ce{CH3 - C - O + \underset{Propyl magnesium iodide}{CH3 - CH2 - CH2 - Mg} - I ->[dry ether] CH3 - C - CH2 - CH2 - CH3->[H2O+] CH3 - C - CH2 - CH2 - CH3 + Mg}\\
\phantom{...........}|\phantom{...................................................}|\phantom{...................................}|\phantom{...........................}\backslash\phantom{...}\\
\phantom{.....................}\ce{\underset{\text{Acetone}}{CH3}}\phantom{.......................................}\ce{\underset{\text{2-Methylpentan-2-ol}}{CH3}}\phantom{......................}\ce{CH3}\phantom{........................}\ce{OH}\phantom{............}
\end{array}\]