Brief Guide to the Nomenclature of Organic Chemistry

Key Contributors

• K.-H. Hellwich (Germany)
• R. M. Hartshorn (New Zealand)
• A. Yerin (Russia)
• T. Damhus (Denmark)
• A. T. Hutton (South Africa)
• Sponsoring Body: IUPAC Division of Chemical Nomenclature and Structure Representation

Introduction

• Universal adoption of agreed nomenclature is crucial for communication in chemical sciences, industry, and regulation.
• IUPAC provides recommendations on nomenclature for organic, inorganic, and polymer chemistry.
• Comprehensive details available in IUPAC’s "Blue Book," "Red Book," and "Purple Book."
• The new Blue Book introduces the Preferred IUPAC Name (PIN) for regulatory purposes.

Substitutive Nomenclature

• Main method for naming organic compounds, particularly those of carbon and Groups 13-17 elements.
• Based on parent compound and characteristic groups with systematic names created through substitution.

Components of Systematic Substitutive Names

• Use of locants, prefixes, and suffixes to indicate structure and substitution.
• Multiplicative prefixes (e.g., di, tri, tetra) convey multiple identical groups.

Creation of Systematic Names

• Steps include determining characteristic groups, senior parent, naming parent hydride, and finalizing name with prefixes and locants.

Characteristic Groups

• Defined by suffix or prefix based on their seniority (e.g., carboxylates, acids, esters, amides).
• CC multiple bonds not viewed as characteristic groups.

Parent Compounds and Parent Hydrides

• Differentiation between acyclic and cyclic parent hydrides (e.g., methane, cyclohexane).
• Use of systematic and non-systematic names for common rings (e.g., benzene).

Acyclic and Monocyclic Parent Hydrides

• Names of saturated carbon chains (alkanes) and monocycles (cycloalkanes) described.

Naming Polycyclic Parent Hydrides

• Bridged, spiro, and fused polycyclic systems have specific naming conventions based on structure.

Saturation and Unsaturation

• Use of "ene" and "yne" endings to indicate double and triple bonds, respectively.
• Hydrogen addition expressed with "hydro" prefixes.

Functional Class Nomenclature

• Preferred for esters and acid halides, among others.
• Functional class names consist of substituent names followed by compound class name.

Specifying Configuration of Stereoisomers

• Stereodescriptors (R/S, E/Z) used for differentiation based on Cahn-Ingold-Prelog rules.

Chemical Abstracts Service (CAS) Names

• CAS registry uses methods similar to IUPAC but with notable differences like CA Index Names.

Graphical Representation

• Structural formulae typically drawn in zig-zag convention, highlighting carbon and hydrogen bonding.

These notes provide a comprehensive guide to the organic chemical nomenclature as outlined by IUPAC, including methods for naming compounds, identifying principal groups, detailing systematic naming conventions, and specifying stereochemistry.