Question: Draw a flow-chart for the Reaction Procedure for Week 1. (3 points) Introduction: The oxidation of alcohols is a very important reaction. Pyridinium chlorochromate (PCC) has been a popular reagent for oxidation of primary alcohols to aldehydes and secondary alcohols to ketones. Unfortunately, it is toxic and carcinogenic (causes cancer). Oxone is a green alternative to PCC. It is a safe and environmentally benign reagent which allows for a less hazardous synthesis. The byproducts of Oxone oxidation pose no immediate threat to aquatic life when disposed. Procedure (Adapted) 1. Running the Reaction: Place 0.50 g of (1S)-Borneol (MW = 154.15 g/mol) into a 25 ml round-bottom flask with a stir bar. Add 2 mL of ethyl acetate (d =0.902 g/ml) to the round-bottom flask and stir. As the solution is stirring, add 1.2 g of Oxone (MW 307.38 g/mol) and 40 mg of NaCl (MW=58.44). Finally, add 1 mL of deionized water and allow the mixture to stir for 30 minutes at room temperature. After 30 minutes, add an additional 15 mg of NaCl and allow the mixture to stir for 10 minutes. 2. Isolation of the Crude Product: Add 7 mL of deionized water to dissolve any salts. Add a spatula tip of sodium bisulfite to reduce trace oxidant. 3. Purification and Isolation of Product: Extract your product mixture in a separatory funnel with ethyl acetate (3 x 5 mL). Wash the combined organic phases with brine before drying over magnesium sulfate. Filter off the magnesium sulfate and transfer your product to a clean, dry and pre-weighed 25 mL round bottom flask. Remember to clean your 25-mL round bottom flask with water first and then acetone last. Use the rotovan to remove the ethyl acetate from your product. 4. Analysis of Product: Determine the weight of the product and calculate the percent yield. Determine the melting point. Obtain an IR of your product. Save your
Lab Data: 0.501 Borreal reasured . 5mL of Brine as quick wash Prewelghed round bottom flask weight 902 density methyl acetate I density of water 347°F melting pt of camphor 175° 0 melting pt of camphor is 22. 1349 Mass of product 176°c melting pt found IS-4879] -179 metting pt:176-177°c)
Green Oxidation of Borneol to Camphor нс. CH HC CH NaBH CH,OH нсон, A Zон нс 0.6 equiv Oxone (12 equy KHSO) 03 equiv NaCl, EROAH,0 H HC н,с OH H 6th ed) Borneol Camphor Isoborneol Required Reading: Background Information but NOT procedure Pavia: 277-290 (289-302 Suggested Reading: Brown, Foote, Iverson and Anslyn. Chapter 16. I Week 1: Pre-Lab Green Oxidation of Borneol to Camphor нс. CH HC CH NaBH CH,OH нсон, A Zон нс 0.6 equiv Oxone (12 equy KHSO) 03 equiv NaC
-
- Site Admin
- Posts: 899603
- Joined: Mon Aug 02, 2021 8:13 am