Synthesis Of Benzoin Lab Report
Synthesis of Benzoin
Date of Experiment: 1-26-15
Chelsea Price
Lab Partner: Joey Simmons
Abstract:
In this experiment, benzoin was synthesized from benzaldehyde, using thiamine hydrochloric acid as a catalyst. The thiamine HCl was deprotonated by sodium hydroxide and acted as a nucleophile to attack the benzaldehyde. A water-cooled condenser was used to heat the solution at reflux. Vacuum filtration was used to wash and dry the product. The benzoin product was recrystallized by dissolving with a H2O/95% ethanol (2:1, v/v) solution and heated to reflux. Vacuum filtration was used to wash and dry the product.
Introduction/Background:
Introduction: Discussion of the mechanism of the performed reaction; discussion …show more content…
There is a formation of a carbene, which is very reactive.
Step 2: nucleophile attack of the benzaldehyde by the deprotonated thiamine:
Step 3: A carbene is formed and attacks another benzaldehyde molecule.
Step 4: thiamine is kicked out
Safety Precautions:
Table 1 contains safety data for all chemicals used in the experiment. Physical and safety data was obtained through Acros Organics [1]. All chemical structures were drawn on ChemDraw Ultra 8.0 [2].
Precautions taken in lab:
Safety goggles were worn in order to protect eyes from harmful irritants.
All open chemicals were handled in a ventilation hood.
Protective clothing (i.e. long pants, closed toed shoes, etc.) was worn.
All chemicals were kept away from open flames.
Material/Chemical List
Glassware
25 mL round bottom flask
100 mL round bottom flask
25 mL filtration Erlenmeyer flask
3- 50 mL beaker
Pasteur …show more content…
The thiamine HCl was dissolved with H2O (2 mL). A stir bar and 95% ethanol (8 mL) were added to the round bottom flask and placed in an ice bath on a stir plate. A Pasteur pipette was used to transfer 2 M NaOH slowly to the flask over a 2 minute time period. The solution turned a dark yellow. The solution continued to stir until the yellow color faded. Benzaldehyde (4 mL) was added to the round bottom flask. The solution turned milky. The round bottom flask was hooked up to a water-cooled condenser to heat the solution. Once the solution began to boil, it was left to reflux for 75
Date of Experiment: 1-26-15
Chelsea Price
Lab Partner: Joey Simmons
Abstract:
In this experiment, benzoin was synthesized from benzaldehyde, using thiamine hydrochloric acid as a catalyst. The thiamine HCl was deprotonated by sodium hydroxide and acted as a nucleophile to attack the benzaldehyde. A water-cooled condenser was used to heat the solution at reflux. Vacuum filtration was used to wash and dry the product. The benzoin product was recrystallized by dissolving with a H2O/95% ethanol (2:1, v/v) solution and heated to reflux. Vacuum filtration was used to wash and dry the product.
Introduction/Background:
Introduction: Discussion of the mechanism of the performed reaction; discussion …show more content…
There is a formation of a carbene, which is very reactive.
Step 2: nucleophile attack of the benzaldehyde by the deprotonated thiamine:
Step 3: A carbene is formed and attacks another benzaldehyde molecule.
Step 4: thiamine is kicked out
Safety Precautions:
Table 1 contains safety data for all chemicals used in the experiment. Physical and safety data was obtained through Acros Organics [1]. All chemical structures were drawn on ChemDraw Ultra 8.0 [2].
Precautions taken in lab:
Safety goggles were worn in order to protect eyes from harmful irritants.
All open chemicals were handled in a ventilation hood.
Protective clothing (i.e. long pants, closed toed shoes, etc.) was worn.
All chemicals were kept away from open flames.
Material/Chemical List
Glassware
25 mL round bottom flask
100 mL round bottom flask
25 mL filtration Erlenmeyer flask
3- 50 mL beaker
Pasteur …show more content…
The thiamine HCl was dissolved with H2O (2 mL). A stir bar and 95% ethanol (8 mL) were added to the round bottom flask and placed in an ice bath on a stir plate. A Pasteur pipette was used to transfer 2 M NaOH slowly to the flask over a 2 minute time period. The solution turned a dark yellow. The solution continued to stir until the yellow color faded. Benzaldehyde (4 mL) was added to the round bottom flask. The solution turned milky. The round bottom flask was hooked up to a water-cooled condenser to heat the solution. Once the solution began to boil, it was left to reflux for 75