# Etymology of saturation degrees (-ane, -ene, -yne) in aliphatic compounds

I like to know where the names for saturated, unsaturated double, and unsaturated triple bonded aliphatic compounds came from.

What is the reason/etymology behind the suffix -ane, -ene, and -yne?

I suppose it parallels something like the inflection-based umlauts in Germanic languages (which may be seen rudimentary in modern English for example in words like mouse/mice) but that is utter speculation. Yet I did not find anything in the web (I think some good extensive Chemical Etymological Encyclopaedia is really missing).

I found the following information through a website linked to Yale University.

The naming structure seems to have evolved from some of the early nonsystematic names given to hydrocarbons. It started with Dumas who in 1835 came up with the name Methylene for the $\ce{CH2}$ radical. The "-ene" suffix is a Greek feminine patronymic which was used to denote that Methylene was the "daughter of" (derived from) the "spirit of wood" or what we now call methanol (Dumas believed methanol had the formula $\ce{CH2\cdot H2O}$).

The naming structure caught on for ethylene since it was related to ethyl(even though the meth- in Methylene came from a Greek work for wine and not the numerical prefix used in methyl).

When the use of these feminine patronymics (-ene, -ine, -one) became common during the 1860s, Hoffman proposed making a consistent nomenclature that followed the standard progression of vowels: a e i o u. This led to the suffixes -ane, -ene, -ine(-yne), -one, and -une to refer to increasingly unsaturated hydrocarbons.

Since -one was already in use for ketone structures, only the first three suffixes caught on.

• This answer probably gets pretty close to the truth (+1). A small comment. The word methylene (Fr. methylène) was probaby co-coined by Dumas and Péligot ($\to$DP) in 1834. As you note, *-ene* is from Greek; however, the interpretation is a bit debatable (imo). DP believed that methylene formed the essential radical of methanol (or wood spirit). It would make more sense for wood spirit to be the 'daugther' than the other way round. In Flood's reference: '*-ene* ... is a name-forming suffix; it has no real meaning in itself.' $|$ ref: W. A. Flood, 1963, The Origins of Chemical Names – Linear Christmas Dec 5 '17 at 20:15

August Wilhelm Hofmann, of rearrangement and elimination fame, suggested the hydrocarbon systematic suffixes in 1866.

http://chem125-oyc.webspace.yale.edu/125/history99/5Valence/Nomenclature/alkanenames.html

http://www.tandfonline.com/doi/full/10.1179/1745823414Y.0000000006

• You should try to avoid answers that are mostly link-only. Usually, you want to give a little more detailed a summary of the links, especially in cases where they aren't accessible or may not be in the future. – Tyberius Dec 2 '17 at 22:26
• The question was answered. One should be careful about "paraphrasing" other's work. The author of the site is extremely knowledgable. – user55119 Dec 2 '17 at 22:57
• But I would argue it doesn't necessarily answer the question. Without going into why he chose those suffixes, it doesn't really inform why Hoffman didn't choose any other possible notation for the suffixes. I would also say we can't really avoid paraphrasing in science. Almost every scientific article I have read has had some citation of prior work that requires summarizing that work and it's implications. You definitely still have to cite your reference in some way, but just pointing to a reference on its own usually isn't enough. – Tyberius Dec 2 '17 at 23:04
• Fair enough. Use caution. – user55119 Dec 2 '17 at 23:08
• I find the linked article (2nd link) a very useful complementation to the answer of Tyberius. – Rudi_Birnbaum Dec 3 '17 at 4:13