solutions to the starting line of the TLC plate. Place the TLC plate in a beaker or jar with a shallow pool of 1:9 ethyl acetate hexane. Visualize using a UV lamp and collect measurements to calculate and compare R values Diagram 1: A is the product and B is the Starting material (2-naphthol)
3) (3 points] Explain why the formation of a side product ) doesn't occur from the use ethanol as our solvent in today's Williamson ether synthesis (Hint: think about the first step of the synthesis and the role of NaOH) 4) (3 points] Explain the two factors that cause the product to precipitate better with the addition of ice to the solution in today's experiment. (Review recrystallization in Pavia for more help)
Procedure: Measure 0.60 g of 2-naphthol into a 50 ml round bottom flask with a stir bar. Add 5.0 mL of absolute ethanol and begin stirring to dissolve the 2-naphthol. Once the 2-naphthol has been suspended in solution add 3-5 pellets of sodium hydroxide, approximately 0.3 g total. After attaching a condenser, bring the mixture to temperature and reflux for 30 min using a hot water bath. CAUTION: Sodium hydroxide is caustic and can damage both the eyes and exposed skin, causing severe burns Once 30 minutes has elapsed allow the solution to briefly cool to 60°C. Once cool remove the condenser and add 0.60 ml of 1-bromobutane via syringe, reattach the condenser and reflux hd solution in the flask for 1 hour. Once the reaction is done refluxing allow to reach 50°C before adding a small amount of ice to the flask (2-5 g) and stir until the ice is completely melted. Allow the reaction to cool in an ice bath for 10 minutes to precipitate as much product as possible, adding a small amount of extra ice or Dl water to the flask if no precipitate is observed. Collect the product via vacuum filtration with a Bachner filter and wash with iced Dl water. After recording the mass of the product, obtain an H-NMR spectra for it using the 400 MHz NMR with the NMR technician's assistance. Also, perform a melting point determination on the crude product For the TLC take a small sample (I speck on the tip of a spatula, 2-6 mg) of the crude product and 2-naphthol and dissolve each in separate beakers or vials in a small amount (1 Pasteur pipette-ful) of ethyl acetate. Use separate glass capillary tubes to apply the two analyte Procedure: Measure 0.60 g of 2-naphthol into a 50 ml round bottom flask with a stir bar. Add 5.0 mL of absolute ethanol
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