Finals

• Alcohols are characterized by one or more hydroxyl groups attached to a carbon atom of a hydrocarbon chain
• IUPAC nomenclature for alcohols

  The hydroxyl group is indicated by the ending —ol
• Common name for alcohols

  The separated word "alcohol" is placed after the name of the alkyl group
• Naming alcohols


  1. Name the longest chain to which the hydroxyl group is attached

  2. Drop the —e, then add —ol

  3. Number the longest chain to give the lower number to the carbon with the attached hydroxyl group

  4. Locate the position of the hydroxyl group

  5. Locate and name any branches attached to the chain
• Number of atoms


  • METH- (1)
  • ETH- (2)
  • PROP- (3)
  • BUT- (4)
  • PENT- (5)
  • HEX (6)
  • HEPT- (7)
  • OCT- (8)
  • NON- (9)
  • DEC- (10)
• Classification of alcohols


  • Depending on whether one, two, or three organic groups are connected to the hydroxyl-bearing carbon atom
  • According to number of hydroxyl groups attached to their molecules
  • Allylic carbon atom (has an adjacent allyl)
  • Benzylic carbon atom (has benzene ring and carbon + OH attached to the ring)
• Physicochemical properties of alcohols

  • Most are colorless liquids at room temperature
  • Higher alcohols (4-10 atoms) are somewhat viscous or oily, have heavy fruity odors
  • Highly branched alcohols with >12 carbon atoms are solids at room temperature
  • Boiling points are much higher than alkanes of similar molecular weight
  • Hydroxyl group is hydrophilic, enhances solubility in water
  • Lower alcohols (up to 4 carbons) are miscible with water
  • Higher molecular weight alcohols are less water-soluble
• Methanol


  • Simplest alcohol (1 carbon containing), formerly produced from wood distillation, now from CO and H2
  • Used to produce formaldehyde and other chemicals, also as solvent and antifreeze
  • Highly toxic, can cause blindness and formaldehyde is carcinogenic
• Ethanol


  • Also known as grain alcohol, produced by fermentation of fruit juices
  • Many sources can provide sugars and starches for fermentation
  • Also manufactured by acid-catalyzed hydration of ethylene
  • Used as solvent, topical antiseptic, and fuel
• Isopropyl alcohol


  • Also known as 2-propanol or rubbing alcohol, manufactured by acid-catalyzed hydration of propene
  • Main component of rubbing alcohol, used in household and personal care products
• Ethylene glycol


  • Used as automotive antifreeze, in hydraulic fluids, printing inks, and paint solvents
  • Polyethylene glycol (PEG) is another variety of ethylene glycol
• Glycerol


  Sweet syrupy substance with three alcohol hydroxyl groups, obtained as a by-product of soap manufacture
• Chemical reactions of alcohols

  • Oxidation
  • Dehydration
  • Substitution
  • Esterification
• Oxidation of alcohols


  1. Alcohols may be oxidized to give ketones, aldehydes, and carboxylic acids

  2. Primary alcohols yield aldehydes, then carboxylic acids

  3. Secondary alcohols yield ketones

  4. Tertiary alcohols usually don't oxidize further without breaking C-C bonds
• Dehydration of alcohols


  1. Removal of the hydroxyl group and a hydrogen atom on the adjacent carbon

  2. Carried out by warming the alcohol in the presence of a strong dehydrating acid

  3. Yields alkenes

  4. Simple alcohols can undergo intermolecular dehydration to give ethers
• Substitution of alcohols


  1. Alkyl halides are synthesized from alcohols, substituting a halogen for the hydroxyl group

  2. Gives best yields with tertiary alcohols

  3. HCl, HBr, HI, thionyl chloride, phosphorus tribromide, and phosphorus triiodide are useful reagents
• Esterification of alcohols


  Alcohols can combine with acids to form carboxylic esters (Fischer esterification)
• Phenols are any organic compounds characterized by a hydroxyl group attached to a carbon atom that is part of an aromatic ring
• Physical properties of phenols

  • Monohydroxy phenols are only slightly soluble in water but miscible with organic solvents
  • Water solubility increases and organic solubility decreases with more hydroxyl groups
  • Simple monohydric phenols are corrosive liquids or low melting solids
  • Dihydric and trihydric phenols are solids
  • Form stronger hydrogen bonds, more soluble in water and higher melting points than alcohols
• Phenol was used as an antiseptic by Joseph Lister in 1865, reducing surgical amputation mortality from 45% to 15%
• Less toxic phenols like n-hexylresorcinol have replaced phenol in some antiseptic applications
• Butylated hydroxytoluene (BHT) is a common low toxicity antioxidant used in foods
• Tyrosine is a standard amino acid found in most proteins
• Epinephrine (adrenaline) is a stimulant hormone produced by the adrenal medulla
• Serotonin is a neurotransmitter in the brain
• Urushiol is an irritant secreted by poison ivy
• Vanillin is the principal flavoring in vanilla, isolated from vanilla beans
• Methyl salicylate has a minty taste and odor, isolated from wintergreen
• Thymol is extracted from thyme and has fungicidal properties
• Eugenol is extracted from clove oil and used as an antiseptic and dental analgesic
• Aldehydes have at least 1 hydrogen atom attached to the carbonyl carbon, which is at the terminal end
• Ketones have two carbon groups attached to the carbonyl carbon, which is in the middle
• Nomenclature for aldehydes


  1. Name the longest chain to which the carbonyl group is attached

  2. Replace -e with -al

  3. Since the aldehyde group is at C1, this number is not included in the name

  4. Locate and name any branches attached to the chain
• Nomenclature for cycloalkane aldehydes

  When the -CHO functional group is attached to a cycloalkane
• Irritant


  Secreted by poison ivy to prevent animal from eating its leaves
• Vanillin


  The principal flavoring in vanilla, isolated from vanilla beans
• Methyl Salicylate


  Has a characteristic minty taste and odor, isolated from wintergreen, usually employed as counter irritant
• Thymol


  Extracted from thyme, fungicidal
• Eugenol


  Extracted from clove oil, antiseptic in mouthwashes, dental analgesic
• Aldehydes


  • Have at least 1 hydrogen atom attached to the carbonyl carbon
  • Terminal carbon