Objective

To purify crude phenylacetaldehyde by distillation.

Procedure

Approximately 20ml of Phenyl acetaldehyde . was taken in a 100ml round bottom flask and distilled at about 400 mm Hg.

Results

Characterization of 35A

HNMR, JCAMP Format HNMR TLC

Discussion

Boiling point of phenylacetaldehyde expected at 400 mm Hg would be 164 C (based on the reported bp of 195C at 1 atm ), which is consistent with with observed distillation temperature at 167 C. However, the HMR of 35A showed many impurities, suggesting that distillation at a lower pressure be attempted. Also it may be necessary to discard a first fraction. When both of these steps are taken, phenylacetaldehyde is obtained pure.

Conclusion

Phenylacetaldehyde could not be purified by distilling under house vacuum (400 mm Hg)

Log

2006-10-20

1. 12:12] Approximately 20ml of Phenylacetaldehyde was taken in a 100ml round bottom flask
2. 12:40] A distillation apparatus was assembled, a hose was connected to the in house vacuum terminal (approximate pressure 400 mm Hg)
3. Phenylacetaldehyde was heated using a thermowell until it started to distill. A stable Ubergang temperature (Tu) of 167 C was recorded.
4. 13:20] A drop in the Tu marked the end of distillation. 35A was obtained as a clear oil.

Tags

Phenylacetaldehyde, InChI=1/C8H8O/c9-7-6-8-4-2-1-3-5-8/h1-5,7H,6H2