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Introductory IUPAC Organic Nomenclature

Alcohols

Nomenclature
Formula
3D structure
Functional class name = alkyl alcohol e.g. ethyl alcohol

Substituent suffix = -ol e.g. ethanol

Substituent prefix = hydroxy-   e.g. hydroxyethane

Structural unit :  alcohols contain R-OH

  • Functional group is an alcohol, therefore suffix = -ol
  • Hydrocarbon structure is an alkane therefore -ane
  • The longest continuous chain is C3 therefore root = prop
  • It doesn't matter which end we number from, the alcohol group locant is 2-
propan-2-ol or 2-propanol
(or isopropanol)
CH3CH(OH)CH3
  • Functional group is an alcohol, therefore suffix = -ol
  • Hydrocarbon structure is an alkene therefore -ane
  • The longest continuous chain is C4 therefore root = but
  • The first point of difference rule requires numbering from the right as drawn to make the alcohol group locant 1-
butan-1-ol or 1-butanol
CH3CH2CH2CH2OH

organic chemistry ©Dr. Ian Hunt, Department of Chemistry University of Calgary