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Basic IUPAC Organic Nomenclature


3D structure
Functional class name = alkyl alkyl ketone

Substituent suffix = -one  e.g. propan-2-one

Substituent prefix = oxo- 

  • Functional group is a ketone, therefore suffix = -one
  • Hydrocarbon structure is an alkane therefore -ane
  • The longest continuous chain is C5 therefore root = pent
  • The first point of difference rule requires numbering from the left as drawn to make the ketone group locant 2-
pentan-2-one or 2-pentanone


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