Experiment 7 Oxidation of Isoborneol PDF

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Brianna Galvan Organic Chem II Experiment 7 Experiment: 7: Oxidation of Isoborneol to Camphor (With Sodium Hypochlorite) Introduction: Oxidation are a critical reaction performed in organic chemistry laboratories. The purpose of this experiment is to generate hypochlorous acid in situ through the combination of sodium hypochlorite and glacial acetic acid. The substrate is isoborneol and the reaction product that will be generated is camphor, which is widely distributed in nature, mainly in trees of the Far East. The isoborneol and camphor are classified as bridged bicyclic species that is commonly converted to an alcohol moiety in ketone in the synthetic lab. MSDS: Isoborneol Formula: C10H18O Molecular Weight:154.25 G/MOLE State:Solid Boiling point:Not available Melting point:212°C-214°C Hazards: Flammable solid Causes skin irritation. Hazardous in case of skin contact (irritant), of eye contact (irritant), of ingestion, of inhalation (lung irritant). Slightly hazardous in case of skin contact (permeator). Severe over-exposure can result in death. Eye: Dust may cause mechanical irritation. Causes skin irritation. May cause irritation of the digestive tract. May cause respiratory tract irritation. Methylene Chloride Formula:CH2Cl2 Molecular Weight: State:Liquid Boiling point:39.75°C Melting point:-97.6°C Hazards: Very hazardous in case of eye contact (irritant), of ingestion, of inhalation. Hazardous in case of skin contact (irritant, permeator). Inflammation of the eye is characterized by redness, watering, and itching. Contact with eyes may cause severe irritation, and possible eye burning. May be absorbed through the skin. Causes irritation with burning pain, itching, and redness. Prolonged exposure may result in skin burns. Causes gastrointestinal irritation with nausea, vomiting and diarrhea. May cause kidney damage. Sodium Hypochlorite Formula:NaCIO Molecular Weight: 98.08 g/mole State:Liquid Boiling point: 40°C Melting point: Not available Hazards: Very hazardous in case of skin contact (irritant), of eye contact (irritant), of ingestion. Hazardous in case of skin contact (corrosive), of eye contact (corrosive). Slightly hazardous in case of inhalation (lung sensitizer). Non-corrosive for lungs. May cause gastrointestinal irritation with nausea, vomiting and diarrhea. May cause severe irritation of the respiratory tract with sore throat, coughing, shortness of breath and delayed lung edema. Glacial Acetic Acid Formula:CHCOOH Molecular Weight: 60.05 g/mole State: Liquid Boiling point: 118.1°C Melting point:16.6°C

Brianna Galvan Organic Chem II Experiment 7 Hazards: Very hazardous in case of skin contact (irritant), of eye contact (irritant), of ingestion, of inhalation. Hazardous in case of skin contact (corrosive, permeator), of eye contact (corrosive). May cause severe and permanent damage to the digestive tract. Causes severe pain, nausea, vomiting, diarrhea, and shock. May cause polyuria, oliguria (excretion of a diminished amount of urine in relation to the fluid intake) and anuria (complete suppression of urination). Rapidly absorbed from the gastrointestinal tract. Materials  Thermometer  Stirring rod  400mL beaker  100mL beaker  Hot plate  Separation Funnel  Filter Flask  Funnel  125 mL Erlenmeyer flask Procedure: 1. Dissolved the 1.25g isoborneol in 4ml glacial acetic acid in 125ml Erlenmeyer’s flask 2. Added 13ml Clorox dropwise in 5 mins. Chilled the reaction with ice 3. keeper the internal temperature of about 15-25 °C 4. Allowed the reaction of a mixture strand to room temperature for an hour. 5. Obtained a positive KI starch test 6. If starch test negative, add small amount of Clorox and continue stir for 20 minutes with step five. 7. Added the statured sodium bisulfate during process 8. After stirring 5mins. Tested the reaction against KI-starch. 9. Poured the reaction mixture over 50mL of brine and ice, collect solid by filtration on funnel. 10. Washed the product with cold temperature of NaHCO3 11. Obtained crude melting point 12. Purification-dissolve solid in 10mL CH2CL2 and place in separatory funnel 13. Performed a wash of organic layer with brine 14. Filtered the organic layer into a clean dry beaker and added the drying salts 15. After a few minutes, the gravity filter dried organic layer into tared round bottom flask and concentrate over a hot plate or hot-water bath in fume hood. That resulted to product and obtain to be yield. Data: Melting point of Camphor=172°C Weight of Beaker=63.00g Weight of Beaker and Camphor=63.90g Weight of Camphor=0.90g Calculations Percent Yield=(experimental/theoretical)(100)=(0.90g/1.256g)(100)=71.65% Percent Error=(experimental-theoretical/theoretical)(100)=(0.09g-1.256g/1.256g)(100)=28.34% Observations The instructor measured the isoborneol and the acetic acid. He then added them both together in the flask and stirred. Next, he added the flask in to the hot water bath and took the tempture. He then added the Clorox dropwise and let it sit for the room temperature. The result of the Clorox was added more of about 10 ml of sodium bisulfite into the solution. Then vacuumed the filtration to separate the solids. He added the sodium bicarbonate and swirled to get the reaming solids and weighted. Conclusions: In conclusion, hypochlorous acid was generated through the combination of sodium hypochlorite and glacial acetic acid. The first time the reaction was tested on the KI strip was negative, so more Clorox

Brianna Galvan Organic Chem II Experiment 7 was added. The second KI test was positive. As a result, it concluded to a longer experimental process, but led to a positive end result. From the 1.256g of Isoborneol and 4 mL glacial acetic acid, 0.90 g camphor was obtained, that led to a percent yield of 71.65% and a percent error of 28.34%. Some possible sources of error may have formed during the addition of extra Clorox and sodium bisulfite at the beginning of the experiment as mentioned before as well as the amount of time it took for the mixture to mix in correctly. Camphor had a melting point of 172C, which is not accurate because the theoretical melting point is between 175- 177C. Reference: Organic Chemistry II Laboratory – CHEM 3125 Lab Manual, Department of Chemistry Texas A&M University – Kingsville, Dr. Jason Abrams YouTube, Tamuk Chemistry Department, 3 July 2020, https://www.youtube.com/watch?v=ssvZMkHJYJo Pre-Lab 1. Draw the mechanism for oxidation of any secondary alcohol with hypochlorous acid. This should be a step-wise curly arrow mechanism. Hypochlorons acid is very strong oxidizing agent after its dissociation HCIOCIO(-)+H(+)

2. Predict the diagnostic peaks in the IR spectrum for the starting material, isoborneol, and the product, camphor.  O-H stretching peak is sharp and prominent for identification of phenol, it arrives in the range of 3650-3600  C-H stretching occur around 300cm-1  C-O vibration bond observed in the range of 1261-1283cm-1  C-O-H bending appears as a broad peak at 1232 cm-1  CO2CO stretching frequency for C-O group is character stics peak 1740-1720cm-1  C-H stretching bond in alkane present at 3000 cm-1; because camphor has axial and equatorial hydrogens. 3. Measure the theoretical yield regarding camphor utilizing particular quantities during the experiment. The reagents borneol, KHSO5, and ethyl acetate react in 1:1:1 mol ratio? 1g*(1mol borneol/154.25g borneol)*(1 mol camphor/1 mol Borneol*152.23g camphor)/1 mol camphor =0.9945 Camphor 0.4575/0.9945*100=46%

Brianna Galvan Organic Chem II Experiment 7 Ethyl acetate has a much lower Mw than borneol and Camphor makes them not a ratio of 1:1:1 Post Lab 4. What is the significance of the KI-starch analysis specified in the experimental produce when the starch paper comes out positive? The amylose component of starch gives rise to the occurrence of the deep blue color when iodine is present. The molecules of iodine enter into the amylose coil. Since Iodine is sparsely dissolvable in water, hence the iodine is dissolved in water that already contains potassium iodide. This lead to the formation of a triiodide ion complex that can dissolve. 5. What is the purpose of adding NaHSO3 at the end of the reaction? NaHSO3 was added at the end of the reaction there was a loss of bus colour, or attainment of end point that arrived with titration. Thereby the indicating the consumption of all the remnant free iodine of bisulfite 6. Provide two variations among reflux and distillation? Reflex is a method to compete a certain chemical reaction whereas distillation is used to take certain components in a mixture. Reflex is usually used for chemical laboratories to dissolve components that makes it difficult to dissolved. Also, that distillation is a liquid that is the process of heating and cooling. The reflux required a round bottom flask, condenser, water bath and a heating. The distillation id required a round bottom flask, Y-apparatus, and condenser connecting to receive a flash....