Procedure

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Calculations for Determining Ratios of Reactants: Group 1 Molar ratios based on the research conducted by Lin, et. al. (2004). 1 mol phenol: 1.5 mol chloroacetic acid: 2.5 mol NaOH
 * Table 1. ** Reagents and amounts used in reaction of phenol and chloroacetic acid: Group 1
 * || **Mass Used (grams)** ||
 * **Phenol** || 1.51 ||
 * **Chloroacetic acid** || 2.7773 ||
 * **Sodium Hydroxide** || 4.854 ||

Starting point=1.5 grams phenol (molar mass =94.11 g/mol) 1.5 g / 94.11 g/mol = 0.0159 = approx. 16 mM phenol

Molar mass chloroacetic acid =94.5 g/mol 16 mM * 1.5 = 24 mM chloroacetic acid 24 mM * 94.5 g/mol = 2268 / 1000 = 2.26 grams chloroacetic acid

Molar mass NaOH = 40 g/mol 16 mM + 24 mM = 40 mM NaOH needed 40 mM * 40 g/mol / 1000 = 1.6 grams NaOH Started with closer to 5 grams due to 30% dilution of NaOH in aqueous solution.


 * Table 2. ** Reagents and amounts used in thymol reaction: Group 2
 * || **Mass (grams)** ||
 * **Thymol** || 1.5 ||
 * **Chloroacetic acid** || 1.28 ||
 * **Sodium hydroxide** || 2.72 ||

1. Obtain quantities of aryl ether, chloroacetic acid, and NaOH listed in Table 1 and 2 above. 2. Place aryl ether, chloroacetic acid, and NaOH into 50 ml round bottom flask. 3. Reflux the mixture for 30-45 minutes. 4. Allow the mixture to cool to room temperature. // Perform Solvent Extraction (steps below) // 5. In a separatory funnel, add the mixture from the round bottom flask, 25 ml ether, and 10 ml sodium bicarbonate (NaHCO3). 6. Cap the funnel with a glass stopper and shake the mixture. Be sure to vent the funnel frequently. 7. When gas no longer escapes from the funnel upon venting, drain the aqueous layer from the separatory funnel into a 250 ml beaker. 8. Add 10 ml NaHCO3 to the separatory funnel and repeat steps 5 and 6. 9. Continue to add 5-10 ml portions of NaHCO3 to funnel until gas is no longer produced after shaking mixture. 10. Add 3 // M // HCl dropwise to 250 ml beaker containing product mixture until pH is less than or equal to 3. Stir the mixture with each addition of HCl. 11. Place the beaker in an ice bath to facilitate crystallization. 12. Filter the solid from the from the solution using a vacuum filtration apparatus. 13. Allow the crystals/solid to dry on a watch glass. Measure the mass of the compound and calculate the yield percentage. 14. Use IR and NMR spectroscopy to analyze the product structure. 15. Dispose of contents from separatory funnel by pouring into organic waste container. Clean the lab area and equipment
 * Procedure **

***Procedural notes for Group 1
 * During reflux, the temperature raised to close to 130 degrees C, had to cool it down.
 * After reflux, only added about 2 mL HCl, and the solution had a pH of below 3. Very little precipitate visisble. Stored for the next week.
 * The next week in lab, tried to crystallize product by putting on ice and scratching bottom of flask. No crytsals appeared.
 * During the second round of solvent extraction using NaHCO3, the separatory funnel exploded while shaking, so we lost the rest of our product. Fortunately, we still had one round of the aqueous layer.
 * In order to evaporate any remaining ether from the aqueous layer and to cut down the volume of the solution to facilitate product crystallization, we boiled the aqueous layer for approx. 15 minutes on low heat and stored. As of 4/5/12, we have not gotten any product crystallization.
 * On 4/12/12, Group 1 dropped the flask containing our aqueous phenoxyacetic acid product on the floor. All product was lost, and no further testing could be completed.