sample2-Carbocations+Oxidation+Data

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1.70 g CrO3, 1.07 g Amberlite || PDC: 2.181 g || Pyridine, 1.35 g CrO3, 1.61 g ||
 * Table 1. ** Reagents, catalysts, and solvents used in reflux or in the reaction.
 * **Reagent & Amount Used/Reflux Time** || **Group 1:** || **Group 2:** || **Group 3:** ||
 * Alcohol || Benzyhdrol, 1.496 g || Benzhydrol, 1.23 g || Benzyl Alcohol, 0.8580 g ||
 * Solvent || Dichlormethane, approx. 40 mL || Dichloromethane, 20 mL || Dichloromethane, 25 mL ||
 * Catalyst || CrO3 in Amberlite:
 * Refluxed for… || 40 minutes, 60 minutes || 35 minutes || N/A ||
 * *Note: After refluxing for 60 minutes, TLC indicated that Group 1 still had a mixture of products. **

Table 2. Eluent ratios used for TLC: testing of products during the progress of the reaction.
 * || **Group 1:** || **Group 2:** || **Group 3:** ||
 * Eluent Ratio 1 || 15% acetone: 85% hexane || 10% acetone: 90% hexane || 40% acetone: 60% hexane ||
 * Eluent Ratio 2 || 30% acetone: 70% hexane || 20% acetone: 80% hexane ||  ||
 * Eluent ratio that produced best separation of compounds || 15% acetone: 85% hexane || 20% acetone: 80% hexane ||  ||
 * Total Volume Eluent || 20 mL || 20 mL || 20 mL ||

Chamber 2=30% acetone, 70% hexane. The spots represent (from right to left): pure benzyhdrol, pure benzophenone, and the product of our reflux reaction of benzhydrol with CrO3 in 1 gram Amberlite after 40 minutes. A mixture of products is evident: not all of the alcohol has reacted.
 * Figure 1. ** Group 1 TLC results from 2/9/12. Chamber 1=15% acetone, 85% hexane.

Data from 2/16/12: Group 1 The plate on the right was developed in 20% acetone, 80% hexane. Less streaking occurred. The spots from left to right are: pure benzhydrol, pure benzophenone, the product of my reaction in CrO3 in Amberlite.
 * Product crytallized upon contact with a TLC spotter. Diluted crystals in 3 mL hexane and 3 drops dichloromethane.
 * Tested product using TLC again to determine purity. Used two chambers: 15% acetone, 85% hexane; 20% acetone, 80% hexane, each with 20 mL total volume. 20% acetone, 80% hexane produced the best separation of products.
 * TLC showed that after gravity filtration and silica gel filtration, the mix of benzhydrol/benzophenone still present (see figure below).
 * Measured melting point of two samples of my product. Melting points: 62.4-63 degrees C and 60.6-60.7 degrees C.
 * Figure 2. ** Group1 TLC from 2/16/12. The plate on the left was developed in 15% acetone, 85% hexane with some streaking.


 * Figure 3. ** TLC of 1000 ppm benzylaldehyde in acetone (stock product) on the left and the Collins reagent solution (solution) on the right after 30 minutes of constant stirring at room temperature. The eluent was composed of 40% acetone and 60% hexane. The two large spots near the top of the TLC plate represent benzylaldehyde. The end product of the Collins oxidation was benzylaldehyde, therefore this indicates a reasonable product yield. The other spots may represent the Collins reagent.