Preparing Tetraphenylcyclopentadienone Most Commonly Known As Tetracyclone

1200 Words Nov 24th, 2016 5 Pages
The purpose of this lab was to prepare tetraphenylcyclopentadienone most commonly known as tetracyclone. This involved a 3-step synthesis over the course of 3 weeks. The first step was the preparation of benzoin, which was completed through self-condensation of benzaldehyde with thiamine used as the base catalyst of the reaction. The next step was the preparation of benzil from the oxidation reaction of benzoin with nitric acid. In the oxidation reaction, the alcohol functional group of benzoin was oxidized to form the carbonyl functional group of benzil, while the nitric acid was reduced into a mixture of nitrogen oxides that formed toxic brown fumes. The final step was the preparation of tetracyclone from the aldol condensation reaction of benzil with dibenzyl ketone in a basic solution.
Preparation of Benzoin
A mixture of thiamine hydrochloride and water were added to a 250 ml round bottom flask and refluxed. When this mixture was dissolved, EtOH was added. The mixture was stirred and cooled in an ice bath. While the mixture was being cooled NaOH was added and this turned the solution yellow. Then a reflux was performed using the cold stirred thiamine solution and 20 ml of benzaldehyde. Adding benzaldehyde to the cold thiamine solution turned the solution cloudy yellow. While refluxing, the solution turned orange. The mixture was then cooled to temperature and crystallization was induced. Then the mixture was vacuum filtered to give the crude solid benzoin.…

Related Documents