This experiment is about the synthesis of 3-nitrobenzaldehyde through nitration. The nitration of benzaldehyde is an example of an electrophilic aromatic substitution reaction, in which a proton of an aromatic ring is replaced by a nitro group. Many aromatic substitution reactions are known to occur when an aromatic substrate is allowed to react with a suitable electrophilic reagent, and many other groups besides nitro may be introduced into the ring. Although the reaction produced a low yield at the end, the yield is calculated from the reaction and limiting reagent.
Keywords: electrophilic aromatic substitution, nitration, aldehyde, nitrating group
Electrophilic substitution happens in many of the …show more content…
When benzaldehyde was added, the solution turned yellow. Nitric compounds are often yellow in color and posses agreeable odor. White fluffy precipitate formed when iced was added to the mixture. And a gum like precipitate formed when it was vacuum filtered. It was then washed with diethyl ether and sodium bicarbonate which dissolved and turned the white precipitate into a pale yellow solution. Petroleum ether or diethyl ether was washed with sodium bicarbonate in order to minimize contamination. The solution transferred to the beaker was allowed to evaporate and a yellow solid was formed.
Table 2. Calculations from the data gathered
Vial with crude sample
Weight of crude sample
The solid was broken down to pieces and transferred to a pre-weighed vial. The weight of the crude sample was then calculated. The theoretical yield was calculated from the reaction of the experiment.
Then, the percent yield was attained from the theoretical yield and the actual yield. The percent yield was 19.85%. One of the reasons for the small yield was that it was not immediately filtered upon the addition of ice.
Nitroaromatic compounds are relatively rare in nature and have been introduced into the environment mainly by human activities. This important class of industrial chemicals is