27960-21-0

Basic information

• Product Name: 3-METHYL-2-HEXENOIC ACID
• Synonyms: TRANS-3-METHYL-2-HEXENOIC ACID;3-METHYL-2-HEXENOIC ACID;3-Methyl-2-hexenoic acid (3:1 mixture of E and Z isomers);3-METHYL-2-HEXENOIC ACID (3:1 MIXTURE OF TRANS- AND CIS- ISOMERS);(Z)-3-Methyl-2-hexenoic acid;(E)-3-methylhex-2-enoic acid;3-Methyl-2E-hexenoic acid;(2E)-3-methyl-2-Hexenoic aci
• CAS NO: 27960-21-0
• Molecular Formula: C₇H₁₂O₂
• Molecular Weight: 128.17
• Mol File: 27960-21-0.mol
• Article Data: 4

Chemical Properties

• Melting Point: -9.25°C (estimate)
• Boiling Point: 237.28°C (estimate)
• Flash Point: 132 °C
• Appearance: /
• Density: 0.9658 (rough estimate)
• Vapor Pressure: 0.0319mmHg at 25°C
• Refractive Index: 1.4273 (estimate)
• PKA: 5.20±0.33(Predicted)
• CAS DataBase Reference: 3-METHYL-2-HEXENOIC ACID(CAS DataBase Reference)
• NIST Chemistry Reference: 3-METHYL-2-HEXENOIC ACID(27960-21-0)
• EPA Substance Registry System: 3-METHYL-2-HEXENOIC ACID(27960-21-0)

Safety Data

• Statements: 34
• Safety Statements: 26-36/37/39
• RIDADR: 3265
• Hazardous Substances Data: 27960-21-0(Hazardous Substances Data)

Usage

General Description

3-Methyl-2-hexenoic acid is a chemical compound with a molecular formula of C7H12O2. It is a colorless liquid with a musty, sweaty, and slightly fruity odor. 3-METHYL-2-HEXENOIC ACID is commonly found in human sweat and is a major contributor to the overall body odor. It is also used in the production of perfumes and as a flavoring agent in the food industry. In addition, 3-methyl-2-hexenoic acid has been studied for its potential as a biomarker for various diseases and metabolic disorders due to its presence in human breath and sweat. Overall, 3-methyl-2-hexenoic acid is a versatile compound with a range of industrial and biological applications.

InChI:InChI=1/C7H12O2/c1-3-4-6(2)5-7(8)9/h5H,3-4H2,1-2H3,(H,8,9)/b6-5+

Synthetic route

(rac)-3-methyl-2-hexenoic acid ethyl ester (22210-21-5) → trans-3-methyl-2-hexenoic acid (27960-21-0)

Conditions	Yield
With potassium hydroxide In ethanol for 1h; Heating;
With barium dihydroxide In water Heating; Yield given;

3-Methylbutenoic acid (541-47-9) + ethyl iodide (75-03-6) → trans-3-methyl-2-hexenoic acid (27960-21-0)

Conditions	Yield
(i) nBuLi, (ii) /BRN= 505934/; Multistep reaction;

Methyl diethylphosphonoacetate (1067-74-9) + 2-Pentanone (107-87-9) → trans-3-methyl-2-hexenoic acid (27960-21-0)

Conditions	Yield
(i) NaOMe, MeOH, (ii) aq. NaOH; Multistep reaction;

2-Pentanone (107-87-9) + PCl3Br2 → trans-3-methyl-2-hexenoic acid (27960-21-0)

Conditions	Yield
Multi-step reaction with 2 steps 1: NaH / tetrahydrofuran 2: aq. KOH / ethanol / 1 h / Heating View Scheme

trans-3-methyl-2-hexenoic acid (27960-21-0) → (2RS,3RS)-2,3-dihydroxy-3-methylhexanoic acid (97209-81-9, 97209-82-0)

Conditions	Yield
With dihydrogen peroxide In formic acid at 40 - 45℃; for 3h;	63%

trans-3-methyl-2-hexenoic acid (27960-21-0) → (2RS,3SR)-2,3-dihydroxy-3-methylhexanoic acid (97209-81-9, 97209-82-0)

Conditions	Yield
With osmium(VIII) oxide; 4-methylmorpholine N-oxide In water; acetone; iso-butanol	49%

trans-3-methyl-2-hexenoic acid (27960-21-0) + chloroformic acid ethyl ester (541-41-3) → N,N-diisopropyl-3-methyl-2E-hexenamide (767329-81-7)

Conditions	Yield
With hydrogenchloride; triethylamine; diisopropylamine	34%

diazomethane (186581-53-3, 908094-01-9) + trans-3-methyl-2-hexenoic acid (27960-21-0) → (E)-3-methyl-hex-2-enoic acid methyl ester (22146-94-7)

diazomethane (186581-53-3, 908094-01-9) + trans-3-methyl-2-hexenoic acid (27960-21-0) + allyl bromide (106-95-6) → 3-Propyl-2,6-heptadiencarbonsaeure-methylester (66052-40-2)

Conditions	Yield
(i) NaH, THF, (ii) LDA, (iii) /BRN= 605308/, (iv) /BRN= 102415/; Multistep reaction;

diazomethane (186581-53-3, 908094-01-9) + trans-3-methyl-2-hexenoic acid (27960-21-0) + allyl bromide (106-95-6) → 2-(1'-Penten-2'-yl)-4-pentensaeureethylester (66052-39-9)

Conditions	Yield
(i) NaH, THF, (ii) LDA, (iii) /BRN= 605308/, (iv) /BRN= 102415/; Multistep reaction;

trans-3-methyl-2-hexenoic acid (27960-21-0) → (E)-3-methylhex-2-en-1-ol (30801-96-8)

Conditions	Yield
(i) LiAlH4, Et2O, (ii) aq. NaOH; Multistep reaction;

trans-3-methyl-2-hexenoic acid (27960-21-0) → diphosphoric acid mono-((E)-3-methyl-hex-2-enyl) ester (24753-28-4)

Conditions	Yield
Multi-step reaction with 2 steps 1: (i) LiAlH4, Et2O, (ii) aq. NaOH 2: (phosphorylation) View Scheme

Upstream product

• 22210-21-5 (rac)-3-methyl-2-hexenoic acid ethyl ester 
• 541-47-9 3-Methylbutenoic acid 
• 75-03-6 ethyl iodide 
• 1067-74-9 Methyl diethylphosphonoacetate 
• 107-87-9 2-Pentanone 

Downstream Products

• 30801-96-8 (E)-3-methylhex-2-en-1-ol 
• 22146-94-7 (E)-3-methyl-hex-2-enoic acid methyl ester 

Relevant articles and documents

INFANT FORMULA CONTAINING AN AROMA COMPOSITION FOR USE AS FRAGRANCE

The invention relates to a nutraceutical composition such as infant formula or infant food comprising a) a defined aroma composition; b) a methodology for developing, maintaining certain aroma constituents in the infant formula and an aroma or fragrance composition to be used to increase the acceptance of a person or an object by the baby or new born.

Synthesis of isoprenoid 1,5-dienes

Aliphatic acids containing an isoprenoid 1,5-diene moiety are prepared in high yields by the selective gamma alkylation of α,β-unsaturated acids with allylic electrophiles. The gamma-regioselectivity of the alkylation is controlled by the use of the dicopper(I) dienolates prepared from the α,β-unsaturated acids. The method offers a particularly facile means for synthesizing isoprenoid 1,5-diene natural products such as farnesoic acid by alkylation of senecioic acid with geranyl bromide; geranoic acid by alkylation of senecioic acid with 3,3-dimethallyl bromide; and dl-lanceol by alkylation of tiglic acid with an allylic bromide derived from dl-limonene. Such products find use in the synthesis of insect pheremones, insect juvenile hormones, and components of perfumes.