Families of Organic Compounds
Introduction to Organic Chemistry
Organic chemistry focuses on the study of carbon-based compounds.
Over 10 million known compounds contain carbon.
Carbon compounds are ubiquitous, found in:
Paint
Gasoline
Plastics
Pesticides
Medicinal drugs
Organic chemistry has direct connections to biochemistry and biological processes.
Families of Organic Compounds
Organic compounds are classified into families based on the presence of specific atoms or functional groups.
Functional Group:
Definition: An atom, group of atoms, or bond that provides the molecule with particular chemical properties.
Families are differentiated according to the atoms present in a molecule.
Hydrocarbons
Hydrocarbons are compounds composed exclusively of carbon and hydrogen atoms.
Hydrocarbons can be categorized into four families:
Families of hydrocarbons interact primarily through London forces, which are weak intermolecular attractions.
Types of Hydrocarbons and Related Bonding
The type of bond present in hydrocarbons influences their molecular shape and bond angles:
Alkanes:
Bond Type: Single bonds (sigma bonds).
Shape: Tetrahedral.
Bond Angle: 109.5°.
Alkenes:
Bond Type: At least one double bond (one sigma and one pi bond).
Shape: Trigonal planar.
Bond Angle: 120°.
Alkynes:
Bond Type: At least one triple bond (one sigma and two pi bonds).
Shape: Linear.
Bond Angle: 180°.
Heteroatoms in Organic Compounds
The remaining families of organic compounds typically contain at least one heteroatom:
Definition: Any atom in the molecule that is not carbon or hydrogen.
Families Containing Oxygen
Compounds containing single bonds to oxygen include the following families:
Alcohols:
Structure: An –OH (hydroxyl) group is attached to an alkane-type carbon.
Phenols:
Structure: An –OH (hydroxyl) group is directly attached to an aromatic ring.
Ethers:
Structure: A C-O-C linkage between carbon atoms.
Families Containing Sulfur
Compounds containing sulfur are similar to those containing oxygen.
Thiols:
Structure: An –SH (sulfhydryl) group attached to an alkane-type carbon.
Sulfides:
Structure: A C-S-C linkage.
Disulfides:
Structure: A C-S-S-C linkage.
Both oxygen and sulfur-containing compounds are commonly found in nature and contribute to various familiar smells.
Families Containing Nitrogen
Compounds containing nitrogen include:
Amines:
Structure: A nitrogen atom is directly attached to one or more alkane-type or aromatic carbon atoms.
Importance: Amines are prevalent in various biochemical compounds.
Families Containing Halogens
Alkyl Halides:
Definition: An alkane-type carbon atom bonded to a halogen atom.
Interactions of Heteroatom Containing Compounds
Oxygen and Nitrogen
Alcohols, phenols, and amines typically exhibit the following interactions:
Hydrogen Bonding:
Occurs when hydrogen is bonded to electronegative atoms such as oxygen or nitrogen.
Molecules such as alcohols, phenols, ethers, amines, and alkyl halides possess polar bonds, leading to dipole-dipole interactions.
Sulfur Compounds
Thiols, sulfides, and disulfides only have nonpolar covalent bonds and interact via London forces.
Note: All molecules can manifest London forces, although the contribution is minimal for small molecules.
Carbonyl Containing Families
Compounds with double bonds to oxygen exhibit specific structures:
Carbonyl Group:
Defined as a C=O bond.
Ketones:
Definition: A carbonyl group that is attached to two other carbon atoms.
Aldehydes:
Definition: A carbonyl group attached to at least one hydrogen atom.
Examples of Organic Compounds
Structures of several organic compounds include:
Progesterone: Structure includes various carbon and functional group arrangements.
Testosterone: A fundamentally similar structure to progesterone, varying through one double bond and specific functional groups.
Vanillin: Notable for its aromatic ring and functional –OH group.
Jasmone: Characterized by unique carbon chain configurations.
Cinnamaldehyde: Contains a carbonyl group and is derived from natural cinnamon.
Visual Reference for Organic Structures
Illustrations of organic compounds can help visualize the arrangement of atoms and functional groups in the discussed families of organic compounds.