Term: alkyl groups
https://doi.org/10.1351/goldbook.A00228

Definition:
Univalent groups derived from alkanes by removal of a hydrogen atom from any carbon atom –CnH2n+1. The groups derived by removal of a hydrogen atom from a terminal carbon atom of unbranched alkanes form a subclass of normal alkyl (n-alkyl) groups H(CH2)n. The groups RCH2, R2CH (R ≠ H), and R3C (R ≠ H) are primary, secondary and tertiary alkyl groups, respectively.


Related Terms:
1) cycloalkyl groups (http://doi.org/10.1351/goldbook.C01498).
2) hydrocarbyl groups (http://doi.org/10.1351/goldbook.H02891).
3) alkanes (http://doi.org/10.1351/goldbook.A00222).

Source: PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1314 (https://doi.org/10.1351/pac199567081307)

Citation: 'alkyl groups' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.A00228

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