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Introductory IUPAC Organic Nomenclature

Ketones

Nomenclature
Formula
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-
2-pentanone or pentan-2-one




CH3CH2CH2C(=O)CH3

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