Alcohols and Their Properties Quiz

Alcohol, Ether & Phenol

• Alcohols have the general formula CnH2n+1 OH
• The -OH group is a functional group for alcohol
• When the -OH group is directly attached to a benzene ring, it's called a phenol
• The old name for benzene is "phene"
• The combination of "phene" and "ol" forms the name "phenol"
• Alcohols contain an -OH group connected to a saturated carbon (sp3)
• Phenols contain an -OH group connected to a carbon in a benzene ring
• The functional group of an alcohol is an -OH (hydroxyl) group bonded to an sp3-hybridized carbon
• The oxygen atom of an alcohol is also sp3 hybridized
• Two sp3 hybrid orbitals of oxygen form s bonds to atoms of carbon and hydrogen
• The remaining two sp3 hybrid orbitals each contain an unshared pair of electrons
• Methanol, CH3OH, has a bond angle of 108.9°, close to the perfectly tetrahedral angle of 109.5°
• Nomenclature of alcohol
  • Step 1: Identify the longest carbon chain containing the -OH group
  • Step 2: Name the parent alkane, replacing the -e ending with -ol
  • Step 3: Add a position number to indicate the location of the -OH group
  • Step 4: If there are multiple -OH groups, use appropriate prefixes (di-, tri-, tetra-)
  • Step 5: Name and number any side-chain branches, adding them to the prefix
• Alcohols are classified as primary (1°), secondary (2°), or tertiary (3°) based on the number of alkyl groups attached to the carbon bearing the -OH group.
• Acid-catalyzed hydration of alkenes involves adding water to an alkene in the presence of an acid catalyst following Markovnikov's rule, although rearrangements are possible.
• Oxymercuration-demercuration is a regioselective method for converting alkenes to alcohols, often favored due to high regioselectivity.
• Hydroboration-oxidation of alkenes adds the elements of water in a regioselective way to an alkene, followed by oxidation and hydrolysis
• Alkyl halides are hydrolyzed to alcohols using aqueous alkali (NaOH or KOH) or moist silver oxide (Ag₂0).
• Aldehydes and ketones can be reduced to alcohols using lithium aluminum hydride (LiAlH₄) or sodium borohydride (NaBH₄)
• Alcohols can undergo dehydration to form ethers when heated with concentrated sulfuric acid or phosphoric acid. Primary and secondary alcohols can be oxidized to aldehydes or ketones. Tertiary alcohols are unreactive to oxidation

Ether

• Ethers are organic compounds with an oxygen atom bonded to two alkyl or aryl groups.
• Nomenclature of ethers typically lists the alkyl groups attached to the oxygen atom in alphabetical order followed by the word "ether".
• More complex ethers use IUPAC substitutive names
• Ethers are often alkoxyalkanes, alkoxyalkenes, or alkoxyarenes
• Ethers resist attack by nucleophiles and bases
• Ethers are frequently used as solvents and in the production of various materials
• Ethers are sometimes used as a starting fluid due to their volatile nature.
• Heating dialkyl ethers with strong acids (HI, HBr, H₂SO₄) cleaves the ether linkage, producing alkyl halides and water.
• Ethers, unlike alcohols, can't form hydrogen bonds with other ether molecules or water

Phenol

• Phenols are compounds where a hydroxyl group (-OH) is directly attached to a benzene ring.
• Their polarity arises from the polar hydroxyl group
• Phenols are present in fragrances, flavorings, preservatives, and germicides
• Phenols are weaker acids than carboxylic acids, but stronger than most alcohols, due to resonance stabilization of the phenolate ion
• Diazonium salts react with water to yield phenols.
• Phenols are more reactive to electrophilic substitution compared to benzene
• Williamson synthesis can convert phenols to ethers
• Treatment with bromine results in the replacement of ortho or para hydrogens in the phenol ring
• The boiling points of simple phenols are substantially higher than those of comparable ethers