Multistep Synthesis Chemistry Experiment
Multistep Synthesis of Tetraphenylcyclopentadienone
In this laboratory experiment a synthesis was performed through several separate steps. The purpose of the experiment was to synthesize tetraphenylcyclopentadienone from benzaldehyde and to run reactions on carbonyl containing compounds. There was a total of three steps that led up to the synthesis of the final product, tetraphenylcyclopentadienone. The first step of the experiment was the condensation of benzaldehyde to yield benzoin. Thiamine catalyst along with water and ethanol were added to the benzaldehyde, then NaOH was added until the solution turned yellow. After recrystallization, the product was benzoin. Step two was the oxidation of benzoin to benzil. Nitric acid was added to the benzoin and heated, this was followed by recrystallization to yield the benzil. In step three the benzil from step two was to be synthesized tetraphenylcyclopentadienone. The benzil and 1,3-diphenylacetone were mixed with ethanol. After heating this, ethanoic KOH was added and the solution was left to reflux. The crystals were washed and collected. This ended the multistep synthesis. The final product was not successfully synthesized due to sources of error during procedures. Therefore, a percent yield was unable to be found. The theoretical melting point for tetraphenylcyclopentadienone 218-220 degrees Celsius.
Introduction: The first step of this experiment was a condensation reaction. Thiamine was the catalyst in this reaction. The thiazolium ion attacks the benzaldehyde. Thiazolium is made in situ by adding base, which was NaOH in this reaction. The thiazolium ion attacks the carbonyl of the benzaldehyde, this served as a nucleophile. This created a negative charge on the benzaldehyde, which attracted another molecule of benzaldehyde. The thiamine leaves the compound and a double oxygen bond is made, leaving this new compound, benzoin, neutral. The second step was an
In this laboratory experiment a synthesis was performed through several separate steps. The purpose of the experiment was to synthesize tetraphenylcyclopentadienone from benzaldehyde and to run reactions on carbonyl containing compounds. There was a total of three steps that led up to the synthesis of the final product, tetraphenylcyclopentadienone. The first step of the experiment was the condensation of benzaldehyde to yield benzoin. Thiamine catalyst along with water and ethanol were added to the benzaldehyde, then NaOH was added until the solution turned yellow. After recrystallization, the product was benzoin. Step two was the oxidation of benzoin to benzil. Nitric acid was added to the benzoin and heated, this was followed by recrystallization to yield the benzil. In step three the benzil from step two was to be synthesized tetraphenylcyclopentadienone. The benzil and 1,3-diphenylacetone were mixed with ethanol. After heating this, ethanoic KOH was added and the solution was left to reflux. The crystals were washed and collected. This ended the multistep synthesis. The final product was not successfully synthesized due to sources of error during procedures. Therefore, a percent yield was unable to be found. The theoretical melting point for tetraphenylcyclopentadienone 218-220 degrees Celsius.
Introduction: The first step of this experiment was a condensation reaction. Thiamine was the catalyst in this reaction. The thiazolium ion attacks the benzaldehyde. Thiazolium is made in situ by adding base, which was NaOH in this reaction. The thiazolium ion attacks the carbonyl of the benzaldehyde, this served as a nucleophile. This created a negative charge on the benzaldehyde, which attracted another molecule of benzaldehyde. The thiamine leaves the compound and a double oxygen bond is made, leaving this new compound, benzoin, neutral. The second step was an