PROPERTIES OF DIFFERENT CLASSES OF ORGANIC COMPOUNDS

• Alkanes


  • Referred to as Paraffins
  • Non-polar substances with low melting point and boiling point
  • Insoluble in water
• Alkenes


  • Hydrocarbons containing double bonds, their functional group
  • Unsaturated hydrocarbons
  • Each double bond corresponds to a loss of 2 hydrogen atoms
• Geometric isomerism


  • E and Z designation used to determine if the high priority groups are on the same side (Zusammen: together) or on the opposite sides (Entgegen: opposite) of the double bond when cis and trans designations are not possible
  • Cahn-Ingold-Prelog Rules (also applied to R and S designations of enantiomers)
• Electrophilic addition of alkenes

  1. Addition of hydrogen halides

  2. Markovnikov's rule: The electrophile adds to the sp2-hybridized carbon bonded to the greater number of hydrogens or has lesser alkyl substituents, the nucleophile adds to the sp2-hybridized carbon bonded to the greater number of alkyl substituents or has lesser hydrogens

  3. Addition of water: Hydration

  4. Addition of halogens: Halogenation

  5. Addition of water via oxymercuration

  6. Addition of borane: Hydroboration-oxidation

  7. Reduction of alkenes: Hydrogenation

  8. Oxidation of alkenes
• Alkynes


  • Also known as acetylenes
  • Non-polar
  • Higher melting point and boiling point than corresponding alkanes and alkenes
• Addition of hydrogen halides to alkynes

  1. Addition of halogens to alkynes

  2. Addition of water to alkynes & keto-enol tautomerism

  3. Hydration of alkynes via hydroboration-oxidation

  4. Reduction of alkynes

  5. Oxidation of alkynes
• Aromatic hydrocarbons


  • Aromatic heterocycles: Cyclic compounds with one or more ring atoms that are not carbon
  • Aromatic polycycles
• Electrophilic aromatic substitution reactions of benzene

  1. Halogenation of benzene

  2. Nitration of benzene

  3. Sulfonation of benzene

  4. Alkylation and acylation of benzene: Friedel-Crafts reactions
• Substituent effects on electrophilic aromatic substitution reactions

  • Inductive electron donation and inductive electron withdrawal
  • Activating substituents
  • Deactivating substituents
  • Ortho-para directors and meta directors
• Organohalides


  Organic compounds with halogen(s)
• Preparation of alkyl halides: Bromination


  1. Reactions of alkyl halides: Grignard's reagents

  2. SN2 reactions

  3. SN1 reactions

  4. E2 reactions

  5. E1 reactions
• Alcohols


  Methanol, ethanol, phenol
• Naming of alcohols


  1. Common names based on alkyl group

  2. Systematic nomenclature adds -ol ending and uses number to identify carbon with OH group
• Preparation of alcohols


  1. Reduction of carbonyl groups

  2. Acid catalyzed-dehydration of alcohols

  3. Oxidation of alcohols
• Epoxides/cyclic ethers


  Have the same chemistry as ethers
• Thiols/mercaptans


  Organic compounds containing a sulfhydryl (-SH) group
• Sulfides/thioethers


  Organic compounds containing a sulfur atom connected to two alkyl or aryl groups
• Phenols


  • Often used as antiseptics
  • Phenol coefficient-measure of antiseptic activity
• Carbonyl compounds and derivatives

  • Aldehydes and ketones are the most widely occurring compounds in nature
  • Aldehydes have a greater partial positive charge on the carbonyl carbon than ketones and have no steric hindrance
• Nucleophilic addition reactions

  1. Hydrate formation

  2. Addition of Grignard reagents and hydride ions

  3. Addition of amines

  4. Addition of alcohols

  5. Addition of phosphorous ylides: The Wittig reaction

  6. Cannizzaro reaction

  7. Reduction of aldehydes and ketones
• Carboxylic acids and derivatives

  • Carboxylic acids are commonly used as source of acyl groups, and hence, are the precursor for several carbonyl-containing compounds
  • Nitriles are close relatives of carboxylic acids
  • Carboxylic acids form carboxylate anions when deprotonated
• Nucleophilic acyl substitution reactions

  1. Conversion of carboxylic acids to acid halides, acid anhydrides, and esters

  2. Reactions of acid halides: Conversion to esters and amides

  3. Reactions of acid anhydrides

  4. Carbonyl condensation reactions: Aldol reactions

  5. Claisen condensation reactions

  6. Conjugate carbonyl additions: Michael reactions
• Amines


  • Organic derivatives of ammonia
  • Most drugs, vitamins, and many other natural products synthesized within plants or animals, are heterocycles
  • Amines are the most common organic bases
  • Amines and carbonyl compounds are the most abundant classes of organic compounds
  • In biological systems, amines occur in their protonated form while carboxylic acids occur in their deprotonated form
• Oxidation of amines


  Tertiary amine oxides undergo Cope Elimination