ALCOHOLS

ALCOHOLS, ETHERS, AND PHENOLS
Juris Marie G. Garcia
Institute of Chemistry, University of the Philippines, Diliman, Quezon City
Date Performed: February 27, 2015
Date Submitted: March 06, 2015

Answers to Questions:

1.) Balanced equations:

A. Lucas Test
Test Sample
Equation
Ethyl Alcohol
C2H5OH + HCl + ZnCl2  C2H5Cl + H2O
Isopropyl Alcohol
(CH3) 2CHOH + HCl  (CH3) 2CHCl + ZnC2 + H2O
Tert-butyl Alcohol
(CH3) 3COH + HCl + ZnCl2  (CH3) 3CCl + ZnCl2 +H2O
Benzyl Alcohol
C6H5CH2OH + HCl + ZnCl2  C6H5CH2Cl +ZnCl2 +H2O

B. Oxidation of Alcohols
Test Sample
Equation
Ethyl Alcohol
C2H5OH + KMnO4  CH3COOH + H2O + MnO2 +K+
Isopropyl Alcohol
2(CH3)2CHOH + KMnO4  2(CH3) 2CO + 2H2O + MnO2 + K+
Tert-butyl Alcohol
No reaction
Benzyl Alcohol
C6H5CH2OH + KMnO4  C6H5COOH + H2O +MnO2 + K+
Diethyl Ether
C4H10O + KMnO4  C4H8O2 + H2O + MnO2 + K+

C. Reaction of Phenols
Test Sample
Equation
Phenol
C6H5OH + 3Br2  C6H5OHBr3 + 3HBr
C6H5OH + KMnO4  C6H4O2 + MnO2 + H2O + K+
FeCl3 + 6C6H5OH  [Fe(OC6H5) 6] 3- + 3H+ + 3Cl- p-Nitrophenol 3C6H5NO3 + FeCl3  Fe(C6H4NO3) 3 + 3HCl
Picric Acid
---
p-Bromophenol
3BrC6H5OH + FeCl3  Fe(BrC6H4O) 3 + 3HCl β-Naphthol 3C10H7OH + FeCl3  Fe(C10H7O)3 + 3HCl

2.) Explain why Lucas test is applicable only to alcohols containing 5 or less carbons
The Lucas reagent is an aqueous solution of strong acid (HCl) and zinc chloride. The alcohol starting material must be sufficiently soluble in aqueous environments for the reaction to take place. Having more than 5 carbons would decrease the compound’s solubility. Only water-soluble alcohols with low molecular weight can be dissolved by the reagent. 3.) Explain why tertiary alcohols and ethers cannot undergo oxidation upon reaction with potassium permanganate.
Tertiary alcohols does not get oxidized by mild oxidizing agents either in aqueous, alkaline or under neutral conditions. They undergo oxidation under acidic condition. Same is true with ethers. Both can only be oxidized under extreme