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Attached is the lab experiment. Here are the questions I need help with:

1. What is the purpose of each of the following steps in this experiment?

a. Adding solid NaCl to the reaction mixture

b. Repeated washings with water, sat'd NAHCO3, and brine

c. the pipet column chromatography

2. Which compound, cyclohexanol or cyclohexanone will have a higher Rf on a TLC plate?

3. What is the advantage of using sodium hypochlorite as an oxidant over CrO3 or Na2Cr2O7 for oxidation?

4. In this reaction, which species is the oxidant and which the reductant?

PROCEDURE OXIDATION OF CYCLOHEXANOL TO CYCLOHEXANONE Set up a water bath as the heat source to warm the reaction mixture on aLABORATORY 9 OXIDATION OF CYCLOHE ISOLATION OF CYCLOHEXANONE 1. Add 0.5g of solid NaCI to a 15-mL Falcon centrifuge tube. AddLABORATORY 9 OXIDATI 3. Add sufficient MTBE/hexanes (1:1) to this column to moisten all of the silica. TIP Alternatively susp

PROCEDURE OXIDATION OF CYCLOHEXANOL TO CYCLOHEXANONE Set up a water bath as the heat source to warm the reaction mixture on a stirrer/ hotplate. Use a 125-mL beaker for the water bath and place it directly on the surface of the hotplate (no need for a sand bath). The oxidant is significantly unstable above 50 °C, so careful temperature control is necessary. 1. To your 5-mL long-necked round-bottomed flask, add 0.150 g of cyclohexa- nol, 0.3 mL of glacial (!!) acetic acid (CH COOH), and 1.0 mL of acetone. 2. Add a magnetic stir bar. 3. Using the black Viton connector, attach an air condenser to the flask and clamp the assembly to a laboratory stand. Wrap the air condenser with a moist paper towel. 4. Immerse the flask in a water bath heated to 45 °C. (Do not go significantly above this temperature.) Start the stirplate at a medium setting. 5. Over the course of 30 minutes add a total of 6 mL of sodium hypochlorite solution (6% aqueous NaOCI, Ultra Clorox) while maintaining stirring and heating for 30 minutes. Addition of 1 mL every 5 minutes is a good pace. (More frequent addition of smaller volumes is better than less frequent addi- tion of larger volumes.) 6. After the last addition continue stirring for 15 minutes. 7. Quench excess oxidant by the dropwise addition of saturated aqueous sodium bisulfite-test with starch-iodide paper and add more sodium bi- sulfite until the starch iodide paper no longer changes color (white blue). (Test your starch iodide paper with bleach first so that you know what kind of color change you are looking for.) 10 ORGANIC CHEMISTRY 272L
LABORATORY 9 OXIDATION OF CYCLOHE ISOLATION OF CYCLOHEXANONE 1. Add 0.5g of solid NaCI to a 15-mL Falcon centrifuge tube. Add the contents of your reaction flask to the sodium chloride and dissolve the solid by agitat- Ing the mixture or by pipetting up and down. 2. Extract the solution with 2 x 2 mL each of CH,Cl2. 3. Wash the combined extracts with 2x 1 mL of H2O. Discard the wash solution. 4. Wash the combined CH.CI extracts with 1 mL satd. NaHCO solution. Mix carefully by pipetting up and down (gas evolution!). Continue until no more gas evolution is observed. 5. Wash the CH2CI extracts with 1 mL of brine. Mix thoroughly to remove as much water from the organic layer as possible. If the DCM layer remains turbid, repeat this step. 6. To the organic layer add four spatula tips of anhydrous Na SO4 and let the mixture sit for 10 minutes with occasional agitation. The dichloromethane should be clear and not cloudy at this point (cloudiness = suspended water). If cloudiness persists add an additional but minimal amount of anhydrous Na2SO4 7. Transfer the dried layer in portions to a fresh dry reaction tube and evaporate the solvent on a water bath. Use a boiling stick! (Do not allow water vapor to enter the tube.) Evaporate after addition of each portion before you add the next one. Do not try to evaporate 4 mL of DCM from a reaction tube in one go. I know it's tempting, but it will likely go off the rails and you lose your product. 8. Dissolve the residue in about 0.3 mL MTBE/hexanes (1:1 (v/v). PURIFICATION OF CYCLOHEXANONE 1. To four dry, clean, numbered reaction tubes add one boiling chip. Weigh the tubes and record the weights in your notebook. Make sure the boiling chip is included in your tared mass of the reaction tube. 2. Fit a disposable pipet with small plug of cotton and then add enough silica to the pipet to create a 1" layer (this should resemble a tiny chromatography column).