What is the structure of the acetal formed by reaction of ethanol with acetophenone?

1 Answer
Nov 17, 2015

The structure of the acetal is #"C"_6"H"_5"C"("CH"_3)("OCH"_2"CH"_3)_2#.

Explanation:

The structure of the acetal is #"C"_6"H"_5"C"("CH"_3)("OCH"_2"CH"_3)_2#.

Ketones react in the presence of acids to form hemiacetals, and the hemiacetals can react further to form acetals.

The general equation is

#"RCOR' + 2R''OH" stackrel("HCl")(→) "RR'C"("OR''")_2 + "H"_2"O"#

The mechanism is

Acetal formation
(from en.wikipedia.org)

In the addition of ethanol to acetophenone, #"R" = "C"_6"H"_5#, #"R'" = "CH"_3#, and #"R''" = "CH"_2"CH"_3#.

So the structure of the acetal is given by the equation

#"C"_6"H"_5"COCH"_3 + "2CH"_3"CH"_2"OH" stackrel("HCl")(→) "C"_6"H"_5"C"("CH"_3)("OCH"_2"CH"_3)_2#