Iso E Super: the velvety woody molecule invented in 1973
Iso E Super is a synthetic molecule created at IFF in 1973, with a smooth woody-amber smell that leaves a velvet-like impression. Perfumers use it as a woody base and a fixative, sometimes at very high doses.
Where does Iso E Super come from?
Iso E Super does not occur in nature. It is a synthetic ketone whose INCI name is "tetramethyl acetyloctahydronaphthalenes", or OTNE for short. According to Wikipedia's article on OTNE, John Hall and James Milton Sanders created it at IFF in 1973, and the patent was granted in 1975. It is produced through a Diels-Alder reaction, and IFF first named it Isocyclemone E.
What does Iso E Super smell like?
Iso E Super smells smooth, woody and ambery, and its maker describes a "velvet" like sensation. The commercial material is a blend of more than twenty isomers: the main one is nearly odourless, and the characteristic scent comes from a minor isomer, Arborone, present at only a few percent. Iso E Super is long-lasting on both skin and fabric.
What does Iso E Super do in a perfume?
Iso E Super works as a woody base and a fixative; when perfumers use a wood scent to fix a formula, it is usually this one. Doses climbed from the late 1980s, and some formulas contain more than half Iso E Super. It also turns up in laundry products, soaps and candles. It sits in the woody family: compare it with natural cedarwood or sandalwood, and with another star molecule, ambroxan.
What should you know about Iso E Super?
Iso E Super is regulated. The IFRA Standards restrict it, with a maximum concentration for each product category, citing dermal sensitization and systemic toxicity. Regulation (EU) 2023/1545 also adds it, under its INCI name, to the fragrance allergens named on EU cosmetic labels. For the bigger story of molecules like this one, read our class on natural versus synthetic.
Further reading
- Tetramethyl acetyloctahydronaphthalenes (Wikipedia, redirected from Iso E Super) en.wikipedia.org
- Perfume (Wikipedia) en.wikipedia.org
- The complete IFRA Standards, up to and including the 51th Amendment (January 2024) ifrafragrance.org
- Commission Regulation (EU) 2023/1545 of 26 July 2023 amending Regulation (EC) No 1223/2009 of the European Parliament and of the Council as regards labelling of fragrance allergens in cosmetic products eur-lex.europa.eu
Iso E Super in the feed
callum.peatin Wearing Fragrance · Glasgow ·
Question
Layering something lighter over birch tar
My birch scent is a running joke at home, and now my partner has asked if I could soften it for her sister's wedding. Can you layer something lighter over a smoky birch scent, or does it all turn to mud?
ingrid_berlin Put the quiet one underneath, not on top. A musk or a soft wood as the bass, then less birch over it.
big_dan_vetiverin Woods, Mosses & Roots · Leeds ·
QuestionIso E Super on a strip, and I smell nothing
Got a smelling strip of Iso E Super from a mate who collects raw materials. Everyone says it's woody and velvety. I sniff it and get almost nothing, then twenty minutes later my jumper smells like a pencil case. Is that normal or is my nose broken?
ingrid_berlin Normal for me too. It sits under everything like a bass note you feel more than hear.
In the Classes
Class no. 4 · 6 min read
Natural vs synthetic fragrance: what chemistry gave perfume
Since the 1860s, perfumery has mixed natural materials with synthetic molecules, and neither is better or safer by default. You'll be able to date the molecules that changed perfume, from coumarin to Iso E Super, and read the word natural on a label without reading too much into it.