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Question
Answer in brief.
Write reaction showing conversion of Acetaldehyde into acetaldehyde dimethyl acetal.
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Solution
Step 1:
\[\begin{array}{cc}
\ce{H3C\phantom{..............................}}\ce{H\phantom{.........}}\\
|\phantom{..................................}|\phantom{.........}\\
\phantom{.}\ce{C = O + CH3 - OH ⇌[dry HCl][dil.HCl] H3C - C - OCH3}\\
\phantom{.}|\phantom{..................................}|\phantom{.........}\\
\phantom{..}\ce{\underset{Acetaldehyde}{H}}\phantom{......................}\ce{\underset{Hemiacetal (unstable)}{OH}}\phantom{........}
\end{array}\]
Step 2:
\[\begin{array}{cc}
\ce{H\phantom{.....................................}}\ce{H\phantom{.........}}\\
|\phantom{......................................}|\phantom{.........}\\
\ce{H3C - C - OCH3 + CH3 - OH ⇌[dry HCl][dil.HCl] H3C - C - OCH3 + H2O}\\
|\phantom{......................................}|\phantom{.........}\\
\ce{\underset{Hemiacetal (unstable)}{H}\phantom{....................}}
\ce{\underset{Acetaldehyde dimethyl acetal (stable)}{OCH3}\phantom{.}}
\end{array}\]
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\[\begin{array}{cc}
\ce{CH3 - CH2 - CH2 - C - CH3 ->[HO - CH2 - CH2 - CH2 - OH][dry HCl] ?}\\
||\phantom{.........}\\
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\end{array}\]
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\[\begin{array}{cc}
\ce{O}\phantom{........}\\
||\phantom{........}\\
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