Lilial
{{Chembox
| ImageFile = Lilial.svg
| IUPACName = 3-(4-tert-Butylphenyl)-2-methylpropanal
| OtherNames = {{unbulleted list|4-tert-Butyl-α-methyl-benzenepropanal | 4-tert-Butyl-α-methyl-hydrocinnamaldehyde | Butylphenyl methylpropional}}
|Section1={{Chembox Identifiers
| CASNo = 80-54-6
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo_Comment = (Racemic)
| CASNo1 = 75166-31-3
| CASNo1_Ref = {{cascite|correct|CAS}}
| CASNo1_Comment = (2R)
| CASNo2 = 75166-30-2
| CASNo2_Ref = {{cascite|correct|CAS}}
| CASNo2_Comment = (2S)
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = T7540GJV69
| UNII_Comment = (Racemic)
| UNII1_Ref = {{fdacite|correct|FDA}}
| UNII1 = 14X71K3AMT
| UNII1_Comment = (2R)
| UNII2_Ref = {{fdacite|correct|FDA}}
| UNII2 = WP1PPC4R9G
| UNII2_Comment = (2S)
| PubChem = 1549660
| PubChem_Comment = (2R)
| PubChem1 = 1715213
| PubChem1_Comment = (2S)
| PubChem2 = 228987
| ChemSpiderID = 1266494
| ChemSpiderID_Comment = (2R)
| ChemSpiderID1 = 1363748
| ChemSpiderID1_Comment = (2S)
| ChemSpiderID2 = 199342
| EINECS = 201-289-8
| UNNumber = 3082
| RTECS = MW4895000
| SMILES = CC(CC1=CC=C(C=C1)C(C)(C)C)C=O
| InChI = 1S/C14H20O/c1-11(10-15)9-12-5-7-13(8-6-12)14(2,3)4/h5-8,10-11H,9H2,1-4H3
| InChIKey = SDQFDHOLCGWZPU-UHFFFAOYSA-N
}}
|Section2={{Chembox Properties
| C=14|H=20|O=1
| Appearance = Clear viscous liquid
| Density = 0.94 g/cm3
| MeltingPtC = -20
| BoilingPtC = 275
| Solubility =0.045 g/L at 20 °C
}}
|Section3={{Chembox Pharmacology
| AdminRoutes = Topical}}
|Section4={{Chembox Related
| OtherFunction_label = aldehydes
| OtherFunction = Bourgeonal
}}
}}
Lilial (a trade name for lily aldehyde, also known as lysmeral or lilestralis) is a chemical compound commonly used as a perfume in cosmetic preparations and laundry powders, often under the name butylphenyl methylpropional. It is an aromatic aldehyde, naturally occurring in crow-dipper and tomato plants,{{cite web | url=https://pubchem.ncbi.nlm.nih.gov/compound/Lilial | title=Lilial }} and produced synthetically in large scale. It was banned for use in cosmetics by the EU in March 2022 after being found to be harmful to fertility.
It is also used as an intermediate in the synthesis of agrochemicals such as fenpropimorph and fenpropidin.
Synthesis
Lilial is produced by the mixed aldol coupling of 4-tert-butylbenzaldehyde (typically as it's methanol acetal) and propionaldehyde, followed by hydrogenation.
Properties
Lilial is commonly produced and sold as a racemic mixture; however, testing has indicated that the different enantiomers of the compound do not contribute equally to its odor. The (R)-enantiomer has a strong floral odor, reminiscent of cyclamen or lily of the valley; whereas the (S)-enantiomer possesses no strong odor.{{cite journal|last1=Bartschat|first1=Dietmar|last2=Bürner|first2=Susanne|last3=Mosandl|first3=A.|last4=Bats|first4=Jan W.|title=Stereoisomeric flavour compounds LXXVI: direct enantioseparation, structure elucidation and structure-function relationship of 4-tert-butyl-α-methyldihydrocinnamaldehyde|journal=Zeitschrift für Lebensmittel-Untersuchung und -Forschung A|volume=205|issue=1|year=1997|pages=76–79|issn=1431-4649|doi=10.1007/s002170050127|s2cid=97399242}}
:File:2-(4-tert-Butylbenzyl)propionaldehyd Formulae V.1.svg{{clear-left}}
Like most aldehydes, lilial is not long term stable and tends to slowly oxidize on storage.
Safety
The Scientific Committee on Consumer Safety (SCCS, scientific committee for consumer safety of the EU Commission) concluded in May 2019 that the use of lilial in both rinse-off and leave-on cosmetics "cannot be considered as safe".
{{cite web |url=https://ec.europa.eu/health/sites/health/files/scientific_committees/consumer_safety/docs/sccs_o_213.pdf |title=OPINION ON the safety of Butylphenyl methylpropional (p-BMHCA) in cosmetic products |date=2019-05-10 |language=en |author=Scientific Committee on Consumer Safety |access-date=2020-05-28 | quote=On individual product basis, Butylphenyl methylpropional (p-BMHCA) (CAS 80-54-6) with alpha-tocopherol at 200 ppm, can be considered safe when used as fragrance ingredient in different cosmetic leave-on and rinse-off type products. However, considering the first-tier deterministic aggregate exposure, arising from the use of different product types together, Butylphenyl methylpropional at the proposed concentrations cannot be considered as safe. }}
After animal studies found it to be toxic for reproduction, it was reclassified as a prohibited substance in the EU, and banned from use in cosmetics as of March 2022.{{cite web |url=https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:32021R1902&from=EN |title=COMMISSION REGULATION (EU) 2021/1902 OF 29 October 2021 amending Annexes II, III and V to Regulation (EC) No 1223/2009 of the European Parliament and of the Council as regards the use of cosmetic products of certain substances classified as carcinogenic, mutagenic or toxic for reproduction |access-date=2022-01-03 | quote= CAS No. 80-54-6}}
It can sometimes act as an allergen and may cause contact dermatitis in susceptible individuals. Lilial was used in many perfumes (examples: Byredo Inflorescence, Salvador Dali Laguna,{{Cite web |title=Купить духи Salvador Dali Laguna — цена туалетной воды, фото, отзывы, описание аромата |url=https://salvador-dali-perfume.ru/product/salvador-dali-laguna/ |access-date=2025-03-12 |website=Salvador Dali |language=ru-RU}} Elizabeth Arden 5th Avenue, etc.) produced before 2022 as a synthetic substitute for the scent of lily of the valley. Due to the ban on the use of lilial, safe analogues are currently used in perfume production.