7.10: The Use of Greek Letters to Denote Substituent Positions

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In the older literature, considerable use is made of the Greek letters \(\alpha\), \(\beta\), \(\gamma\), and so on, to designate successive positions along a hydrocarbon chain. The carbon directly attached to the principal function group is denoted as \(\alpha\), the second carbon is \(\beta\), and so on down the chain:

Roberts and Caserio Screenshot 7-10-1.png

The omega (\(\omega\)) position is sometimes used to designate the last position along the chain regardless of its length. Thus \(\omega\)-bromohexanoic acid is 6-bromohexanoic acid. In general, the use of Greek letters in the naming of compounds is to be avoided. Because the usage is widespread, cognizance of the system is important, but systematic naming and numbering systems should be used whenever possible.

Contributors and Attributions

John D. Robert and Marjorie C. Caserio (1977) Basic Principles of Organic Chemistry, second edition. W. A. Benjamin, Inc. , Menlo Park, CA. ISBN 0-8053-8329-8. This content is copyrighted under the following conditions, "You are granted permission for individual, educational, research and non-commercial reproduction, distribution, display and performance of this work in any format."