Basic IUPAC Organic Nomenclature

Thiols

Nomenclature	Formula	3D structure
Functional class name = alkyl mercaptan Substituent suffix = -thiol e.g. ethanethiol Substituent prefix = sulfanyl-   e.g. Structural unit :  alcohols contain R-SH Note: Thiols are the sulfur analogues of alcohols

• The root name is based on the longest chain with the -SH attached.
• The chain is numbered so as to give the thiol unit the lowest possible number.
  
• The thiol suffix is appeneded after the hydrocarbon suffix : e.g.  -ane + -thiol = -anethiol or -ene + thiol = -enethiol.
  

Functional group is a thiol, therefore suffix = -thiol 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- propane-2-thiol or 2-propanethiol

CH3CH(SH)CH3

©Dr. Ian Hunt, Department of Chemistry