Citronellal

{{distinguish|Citronellol|Citronella (disambiguation){{!}}Citronella}}

{{Use dmy dates|date=March 2021}}

{{chembox

| Watchedfields = changed

| verifiedrevid = 443528634

| Reference =Citronellal, The Merck Index, 12th Edition

| Name = Citronellal

| ImageFile_Ref = {{chemboximage|correct|??}}

| ImageFile = Structural formula of (RS)-Citronellal.svg

| ImageSize = 150

| ImageAlt = Skeletal formula of (+)-citronellal

| ImageFile1 = (+)-Citronellal 3D ball.png

| ImageAlt1 = Ball-and-stick model of the (+)-citronellal molecule

| ImageCaption1 = (+)-Citronellal

| ImageFile2 = (-)-Citronellal 3D ball.png

| ImageAlt2 = Ball-and-stick model of the (-)-citronellal molecule

| ImageCaption2 = (-)-Citronellal

| IUPACName = 3,7-dimethyloct-6-enal

|Section1={{Chembox Identifiers

| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

| ChemSpiderID = 7506

| PubChem = 7794

| UNII_Ref = {{fdacite|correct|FDA}}

| UNII = QB99VZZ7GZ

| KEGG_Ref = {{keggcite|correct|kegg}}

| KEGG = C17384

| Beilstein = 1209447 1720789

| Gmelin = 1521962

| InChI = 1/C10H18O/c1-9(2)5-4-6-10(3)7-8-11/h5,8,10H,4,6-7H2,1-3H3

| InChIKey = NEHNMFOYXAPHSD-UHFFFAOYAH

| SMILES1 = O=CCC(CC/C=C(/C)C)C

| ChEMBL_Ref = {{ebicite|correct|EBI}}

| ChEMBL = 447944

| StdInChI_Ref = {{stdinchicite|correct|chemspider}}

| StdInChI = 1S/C10H18O/c1-9(2)5-4-6-10(3)7-8-11/h5,8,10H,4,6-7H2,1-3H3

| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}

| StdInChIKey = NEHNMFOYXAPHSD-UHFFFAOYSA-N

| CASNo_Ref = {{cascite|correct|CAS}}

| CASNo = 106-23-0

| EINECS = 203-376-6

| ChEBI_Ref = {{ebicite|correct|EBI}}

| ChEBI = 47856

| SMILES = C/C(C)=C/CCC(C)CC=O

}}

|Section2={{Chembox Properties

| Formula = C₁₀H₁₈O

| MolarMass = 154.25 g/mol

| Density = 0.855 g/cm³

| BoilingPtC = 201 to 207

}}

|Section3={{Chembox Hazards

| GHSPictograms = {{GHS exclamation mark}} {{GHS environment}}{{GESTIS|ZVG=491257 |CAS=123-72-8 |Name=Citronellal |Date=13 March 2020 }}

| GHSSignalWord = Warning

| HPhrases = {{H-phrases|315|317|411}}

| PPhrases = {{P-phrases|262|273|280|302+352}}

}}

|Section4={{Chembox Related

| OtherFunction_label = alkenals

| OtherFunction = Citral

Methacrolein

trans-2-Methyl-2-butenal

}}

}}

Citronellal or rhodinal (C₁₀H₁₈O) is a monoterpenoid aldehyde, the main component in the mixture of terpenoid chemical compounds that give citronella oil its distinctive lemon scent.

Citronellal is a main isolate in distilled oils from the plants Cymbopogon (excepting C. citratus, culinary lemongrass),{{cite journal | doi = 10.1002/ffj.1144 | title = Volatile constituents of Cymbopogon nardus (Linn.) Rendle | year = 2003 | last1 = Mahalwal | first1 = Vijender S. | last2 = Ali | first2 = Mohd. | journal = Flavour and Fragrance Journal | volume = 18 | pages = 73–76| doi-access = free }} lemon-scented gum, and lemon-scented teatree. The (S)-(−)-enantiomer of citronellal makes up to 80% of the oil from kaffir lime leaves and is the compound responsible for its characteristic aroma.

Citronellal has insect repellent properties, and research shows high repellent effectiveness against mosquitoes.{{cite journal |author1=Jeong-Kyu KIM |author2=Chang-Soo KANG |author3=Jong-Kwon LEE |author4=Young-Ran KIM |author5=Hye-Yun HAN |author6=Hwa Kyung YUN | title = Evaluation of Repellency Effect of Two Natural Aroma Mosquito Repellent Compounds, Citronella and Citronellal | journal = Entomological Research | volume = 35 | issue = 2 | pages = 117–120 | year = 2005 | doi = 10.1111/j.1748-5967.2005.tb00146.x|s2cid=85112045 }} Another research shows that citronellal has strong antifungal qualities.{{cite journal | author = Kazuhiko NAKAHARA, Najeeb S. ALZOREKY1, Tadashi YOSHIHASHI, Huong T. T. NGUYEN and Gassinee TRAKOONTIVAKORN | title = Chemical Composition and Antifungal Activity of Essential Oil from Cymbopogon nardus (Citronella Grass) | journal = JARQ | year = 2003 | volume = 37 | issue = 4}}