February 18, 2015
- Analyze purified benzophenone sample using NMR from February 4, 2015
- Extract and Purify reaction mixture started on February 10, 2015
- The sample was purified by column chromatography using hexane and chloroform (4:1) as an eluent. A TLC plate was spotted with the fractions collected to determine which fraction the product was is.
- The suspected benzophenone product was dried over a watch glass and dissolved in CDCl3.
- The sample was transferred to an NMR tube and analyzed.
- Another oxidation reaction was setup on February 10, 2015, and stopped on February 11th.
- The reaction sat for one week before being analyzed
- A TLC plate was spotted with starting material and the products to determine if any of the expected product (benzophenone) formed. The TLC plate showed very little separation between them.
- Excess water was added to the reaction mixture and the solid white precipitate was recovered by vacuum filtration. The white precipitate was dissolved in ethyl acetate and centrifuged to remove the gold nanoparticles.
- The sample was not purified but ran NMR just to compare it to the spectrum of benzophenone synthesized on February 4, 2015.
The following shows the proton NMR spectra of suspected benzophenone from February 4th (Trial 1) and February 10th(Trial 2)
Trial 2 Spectrum
Based on the actual NMR spectrum of benzhydrol and benzophenone, it can be concluded that all of the product (benzophenone) did not form or convert completely. It is possible that the reaction did not completely finish because of the little amount of gold nanoparticles added as a catalyst. Future reactions should include either more catalyst in volume added to the reaction mixture or the adding more H2O2 (oxidizer).