Post Lab: Aromatic Hydrocarbons and Alcohols & Phenols PDF

Expt. No. 9 AROMATIC HYDROCARBONS  Experimental Results: C6H5CH3 + CHCl3 → AlCl 3 C6H5CH2CHCl2 + HCl QUESTIONS 1. What are the main sources of aromatic hydrocarbons? PETROLEUM AND COAL TAR 2. Describe two ways of preparing toluene....

Expt. No. 9 AROMATIC HYDROCARBONS  Experimental Results: C6H5CH3 + CHCl3 → AlCl 3 C6H5CH2CHCl2 + HCl QUESTIONS 1. What are the main sources of aromatic hydrocarbons? PETROLEUM AND COAL TAR 2. Describe two ways of preparing toluene. a) Friedel-Crafts Alkylation C6H6 + CH3Cl Anhydrous → AlCl3 C6H5CH3 + HCl b) Wurtz-Fittig Reaction Na C6H5Br + CH3Br → C6H5CH3 + Br2 Dry ether …Questions 3. Benzene is the parent of all aromatic compounds. What are the ill effects of benzene in the body? a) Short term breathing of high levels may cause death b) Low levels may cause drowsiness, dizziness, rapid heart rate, headaches, tremors, confusion, and unconsciousness. c) If eaten, can cause vomiting, stomach irritation, dizziness, sleepiness, convulsion, and death. d) Bone marrow damage and decrease in RBCs leading to anemia, leading to leukemia e) Depress immune system, increasing infection …Questions 4. (a) A circle (ring) within a hexagon is often used to represent an aromatic carbon ring. What does the circle represent? That all the bonds are equal (b) What is the shortcoming of representing the bonding in a benzene ring using alternating single and double carbon-carbon bonds?  Single and double bonds have different lengths. …Questions 5. The Friedel-Crafts Alkylation of p-xylene with n-propyl bromide can result in an isopropyl as well as n-propyl substitution. (a) Write the chemical equation involved in this reaction. …Questions 5. The Friedel-Crafts Alkylation of p-xylene with n-propyl bromide can result in an isopropyl as well as n-propyl substitution. (b) Which will be the major and minor product? What do you expect will be the ratio of n-propyl to isopropyl substitution for p- xylene? Major product: Isopropyl substituted Minor product: n-propyl substituted ADDITIONAL NOTES ON AROMATICS:  Expt. No. 10 ALCOHOLS and PHENOLS Experimental Results Conclusion: Increased number of –OH, increased solubility Oxidation of alcohols: 1O alcohol [O] aldehyde [O] carboxylic acid Ex: CH3CH2OH [O] CH3 CHO [O] CH3COOH 2O alcohol [O] ketone Ex: CH3CHCH3 [O] CH3 C CH3 | ║ OH O 3O alcohol [O] NO REACTION Iodoform test - formation of yellow precipitate (CHI3) CH3CH2OH + 4 I2 + 6 NaOH → CHI3 (↓) + HCOONa + 5 NaI + 5 H2O Test for Phenolic Compounds 1)FeCl3 – produces violet coloration 2)MILLON’S TEST – specific test for phenolic amino acids; produces a red colored solution Classification of alcohols 1) Lucas’ reagent (rates of reaction) 3O > 2 O > 1 O 3O alcohols forms 2 layers or cloudiness on immediate reaction towards Lucas’ reagent 2) Oxidation rate: 1O > 2O > 3O (no reaction) - Greenish black solution is formed 3) Ferric Chloride test: Isoproyl --- no reaaction Alcohols with aromatic rings ---- formation of purple solution  ADDITIONAL NOTES Types of alcohols: Example A) aliphatic CH3OH; CH3 CH2OH; CH3CHOHCH3 B) alicyclic OH C) aromatic CH2OH D) polyhydric CH2 (OH) CH(OH) CH2(OH) ADDITIONAL NOTES