127-51-5

Basic information

• Product Name: ALPHA-ISO-METHYLIONONE
• Synonyms: (3E)-3-Methyl-4-(2,6,6-trimethyl-2-cyclohexen-1-yl)-3-buten-2-one;3-methyl-4-(2,6,6;3-methyl-4-(2,6,6-trimethyl-2-cyclohexen-1-yl)-3-buten-2-on;8-Methyl-alpha-ionone;alpha-Ionone, isomethyl-;iso-alpha-methyl ionone;Methyl-alpha-isoionone;α-Isomethylionone
• CAS NO: 127-51-5
• Molecular Formula: C₁₄H₂₂O
• Molecular Weight: 206.32
• EINECS: 204-846-3
• Mol File: 127-51-5.mol
• Article Data: 4

Chemical Properties

• Boiling Point: 121-122℃ (9 Torr)
• Flash Point: 122.1 °C
• Appearance: /
• Density: 0.93 g/mL at 20 °C(lit.)
• Vapor Pressure: 0.00282mmHg at 25°C
• Refractive Index: 1.50188 (589.3 nm 20℃)
• Storage Temp.: room temp
• Water Solubility: 27.953mg/L at 25℃
• CAS DataBase Reference: ALPHA-ISO-METHYLIONONE(CAS DataBase Reference)
• NIST Chemistry Reference: ALPHA-ISO-METHYLIONONE(127-51-5)
• EPA Substance Registry System: ALPHA-ISO-METHYLIONONE(127-51-5)

Safety Data

• Hazard Codes: Xi
• Statements: 43
• Safety Statements: 24/25-36/37
• RIDADR: UN1230 - class 3 - PG 2 - Methanol, solution
• WGK Germany: 2
• Hazardous Substances Data: 127-51-5(Hazardous Substances Data)

Usage

Description

α-Isomethylionone has a fine violet and orris-like odor. This substance may be synthesized by condensation of citral with methyl ethyl ketone controlling the ratio between the n- and iso-forms; the methyl pseudo-ionone obtained is then subjected to ring closure, using strong alkali and high temperature (thus favoring the formation of the normal α- and β-methylionones) or with quaternary ammonium base (thus favoring the formation of wo-forms); See also monographs of α- and β-ionone and methyl α-, β-, and γ-ionones.

Chemical Properties

α-Isomethylionone has a fine violet and orris-like odor.

Preparation

By condensation of citral with methyl ethyl ketone controlling the ratio between the n- and iso-forms; the methyl pseudoionone obtained is then subjected to ring closure, using strong alkali and high temperature (thus favoring the formation of iso-forms); See also monographs of α-, β-, and γ-ionones.

Flammability and Explosibility

Notclassified

Contact allergens

As a fragrance allergen, a-isomethylionone has to be mentioned by name in cosmetics within the EU.

InChI:InChI=1/C14H22O/c1-10-7-6-8-14(4,5)13(10)9-11(2)12(3)15/h7,9,13H,6,8H2,1-5H3/b11-9+

Upstream product

• 26651-96-7 7,11-dimethyl-dodeca-4,6,10-trien-3-one 
• 107-86-8 3,3-dimethyl acrylaldehyde 
• 14505-74-9 α-cyclocitral 
• 78-93-3 butanone 
• 141-10-6 pseudoionone 
• 29021-40-7 3,7-Dimethyl-7-octen-1-in-3-ol 
• 28049-52-7 3,6,10-trimethyl-undeca-3,5,10-trien-2-one 

Downstream Products

• 13215-88-8 4-(But-2-enylidene)-3,5,5-trimethylcyclohex-2-enone 
• 1345865-18-0 (E)-2-(5-(1-(2,6,6-trimethylcyclohex-2-enyl)prop-1-en-2-yl)-1H-pyrazol-1-yl)pyridine 

Relevant articles and documents

Synthesis method of alpha-cyclocitral

The invention discloses a synthesis method of alpha-cyclocitral. The method comprises the steps of (1) carrying out Diels-Alder reaction on 1,3-pentadiene and methylcrotonaldehyde under the catalysisof lewis acid to obtain a 2,6,6-trimethyl-3-cyclohexenyl formaldehyde crude product; (2) carrying out isomerization reaction on the 2,6,6-trimethyl-3-cyclohexenyl formaldehyde crude product obtained in step (1) under the catalysis of a catalyzer to generate an alpha-cyclocitral crude product. The method provided by the invention is easy to get reaction raw materials, mild in conditions, easy to control, free of generating byproducts, simple in process, favorable in industrial production, green and environmentally friendly.

CONTINUOUS PROCESS FOR PRODUCING PSEUDOIONONES AND IONONES

The invention relates to a continuous process for producing pseudoionones of general formulas (I) and (I′) as well as isomers thereof, whereby: R1represents CH3 or (a); R2 and R3 represent hydrogen, CH3 or C2H5, and; R4 and R5represent hydrogen or CH3. These pseudoionones are produced by reacting an aldehyde of formula (II) with an excess of a ketone of general formula (III), whereby R1, R2 and R3 have the aforementioned meanings, in the presence of water and alkali hydroxide at an increased temperature and in a homogeneous solution. The inventive process is characterized in that: a) the intermixing of the homogeneous solution consisting of aldehyde, ketone and aqueous alkali lye occurs at a temperature ranging from 10 to 120 °C; b) the undissolved water and alkali hydroxide contained in the reaction mixture are subsequently separated out; c) while avoiding back mixing, the homogeneous reaction mixture is then guided through a reactor, which permits a residence time ranging from 2 to 300 minutes, at a temperature that is 10 to 120 °C higher than the boiling point of the lowest-boiling component and under a vapor pressure p ranging from 106 to 107 Pa; d) the reaction mixture is cooled by expansion; e) ketone is removed from the reaction mixture using vapor flowing in the opposite direction and; f) the raw product is dried and rid from excessive aldehyde and secondary components via a rectification column.