13494-07-0

Basic information

• Product Name: 3,5-Dimethyl-1,2-cyclopentanedione
• Synonyms: 2-Cyclopentanedione,3,5-dimethyl-1;3,5-dimethyl-2-cyclopentanedione;CORONOL;FEMA 3269;3,5-DIMETHYL-2-HYDROXY-2-CYCLOPENTENYL-1-ONE;3,5-DIMETHYL-1,2-CYCLOPENTADIONE;3,5-DIMETHYL-1,2-CYCLOPENTANEDIONE;3,5-dimethylcyclopentane-1,2-dione
• CAS NO: 13494-07-0
• Molecular Formula: C₇H₁₀O₂
• Molecular Weight: 126.15
• EINECS: 236-811-3
• Product Categories: Alphabetical Listings;C-D;Flavors and Fragrances
• Mol File: 13494-07-0.mol
• Article Data: 1

Chemical Properties

• Melting Point: 87-95 °C(lit.)
• Boiling Point: 187.365 °C at 760 mmHg
• Flash Point: 63.628 °C
• Appearance: white to pale yellow crystalline powder
• Density: 1.037 g/cm³
• Vapor Pressure: 0.633mmHg at 25°C
• Refractive Index: 1.45
• CAS DataBase Reference: 3,5-Dimethyl-1,2-cyclopentanedione(CAS DataBase Reference)
• NIST Chemistry Reference: 3,5-Dimethyl-1,2-cyclopentanedione(13494-07-0)
• EPA Substance Registry System: 3,5-Dimethyl-1,2-cyclopentanedione(13494-07-0)

Safety Data

• WGK Germany: 3
• Hazardous Substances Data: 13494-07-0(Hazardous Substances Data)

Usage

Description

3,5-Dimethyl-1,2-cyclopentanedione is an organic compound with a molecular formula of C7H10O2. It is a white to pale yellow crystalline powder that is known for its distinct brown, sweet, sugary, maple, and caramellic taste characteristics at a concentration of 10 ppm.

Uses

Used in Flavor and Fragrance Industry:
3,5-Dimethyl-1,2-cyclopentanedione is used as a flavoring agent for its brown, sweet, sugary, maple, and caramellic taste characteristics. It is particularly useful in the creation of artificial flavors that mimic the taste of natural products, enhancing the overall flavor profile of various food and beverage products.
Used in Aroma Industry:
3,5-Dimethyl-1,2-cyclopentanedione is also utilized as a component in the fragrance industry, where it contributes to the development of complex and pleasant scents. Its unique aroma profile makes it a valuable addition to perfumes, colognes, and other scented products.
Used in Food Industry:
In the food industry, 3,5-Dimethyl-1,2-cyclopentanedione is used as an additive to enhance the taste and aroma of various products. Its natural occurrence in coffee aroma and cooked pork makes it an ideal choice for improving the flavor of these and other similar food items.
Used in Chemical Research:
3,5-Dimethyl-1,2-cyclopentanedione is also employed in chemical research and development, where it serves as a starting material or intermediate for the synthesis of more complex organic compounds. Its unique chemical properties make it a valuable tool in the creation of new molecules with potential applications in various industries.

Preparation

By direct alkylation of the methyl ester of the commercially available 3-methylcyclo-pent-2-en-2-ol-1-one, followed by the cleavage of the ether function.

InChI:InChI=1/C7H10O2/c1-4-3-5(2)7(9)6(4)8/h4-5H,3H2,1-2H3

Synthetic route

3,5-dimethyl-cyclopent-3-ene-1,2-dione (2687-69-6) → 3,5-dimethyl-1,2-cyclopentanedione (13494-07-0)

Conditions	Yield
With Lindlar's catalyst; diethyl ether Hydrogenation;

4,5-dioxo-cyclopentane-1,3-dicarboxylic acid diethyl ester (10088-87-6) + methyl iodide (74-88-4) → 3,5-dimethyl-1,2-cyclopentanedione (13494-07-0)

Conditions	Yield
With sodium ethanolate Erhitzen des Reaktionsprodukts mit wss. H2SO4;

2-methoxy-3,5-dimethyl-cyclopent-2-enone → 3,5-dimethyl-1,2-cyclopentanedione (13494-07-0)

Conditions	Yield
With hydrogen iodide

5,6-diamino-3-(4-chlorobenzyl)-1-propylpyrimidine-2,4(1H,3H)-dione (1073239-44-7) + 3,5-dimethyl-1,2-cyclopentanedione (13494-07-0) → 3-(4-chlorobenzyl)-6,8-dimethyl-1-propyl-7,8-dihydro-1H-cyclopenta[g]pteridine-2,4(3H,6H)-dione (1135922-51-8)

Conditions	Yield
With acetic acid In methanol; DCM at 160℃; for 0.666667h; Microwave irradiation;	32%

3,5-dimethyl-1,2-cyclopentanedione (13494-07-0) + acetic anhydride (108-24-7) → 2-acetoxy-3,5-dimethyl-cyclopent-2-enone

3,5-dimethyl-1,2-cyclopentanedione (13494-07-0) + N,N-Dimethylthiocarbamoyl chloride (16420-13-6) → 3,5-dimethyl-2-<(dimethylthiocarbamoyl)oxy>-2-cyclopenten-1-one (110874-93-6)

Conditions	Yield
With lithium hydroxide In chloroform for 3h; Ambient temperature;

3,5-dimethyl-1,2-cyclopentanedione (13494-07-0) → 2,4-dimethyl-4-<(dimethylcarbamoyl)thio>-2-cyclopenten-1-one (110874-92-5)

Conditions	Yield
Multi-step reaction with 2 steps 1: aq. lithium hydroxide / CHCl3 / 3 h / Ambient temperature 2: 37 percent / lithium chloride, acetic acid / 1.5 h / Heating View Scheme

3,5-dimethyl-1,2-cyclopentanedione (13494-07-0) → 2-hydroxy-3,5-dimethyl-cyclopentanone

Conditions	Yield
Multi-step reaction with 3 steps 2: platinum; dioxane / Hydrogenation 3: aqueous KOH View Scheme

3,5-dimethyl-1,2-cyclopentanedione (13494-07-0) → 2-acetoxy-3,5-dimethyl-cyclopentanone (859318-83-5)

Conditions	Yield
Multi-step reaction with 2 steps 2: platinum; dioxane / Hydrogenation View Scheme

2,3-diamino-N-(4-methyl-cyclohexyl)-propionamide + 3,5-dimethyl-1,2-cyclopentanedione (13494-07-0) → 7-hydroxy-5, 7-dimethyl-N-(trans-4-methylcyclohexyl)-6, 7-dihydro-5H-CYCLOPENTA [B] PYRAZINE-2-CARBOXAMIDE

Conditions	Yield
With pyridinium p-toluenesulfonate In benzene Heating / reflux;

3,5-dimethyl-1,2-cyclopentanedione (13494-07-0) + 2,6-diisopropylbenzenamine (24544-04-5) + p-toluenesulfonic acid monohydrate (6192-52-5) → 2,(2,6-diisopropylphenylamino)-3,5-dimethylcyclopent-2-enone (1210405-77-8)

Conditions	Yield
In toluene	2.5156 g (73.9%)
In toluene	2.5156 g (73.9%)

3,5-dimethyl-1,2-cyclopentanedione (13494-07-0) + 2,6-diisopropylbenzenamine (24544-04-5) → (E)-N-(5-(butylimino)-2,4-dimethylcyclopent-1-enyl)-2,6-diisopropylaniline (1210405-88-1)

Conditions	Yield
Multi-step reaction with 2 steps 1: toluene 2: N-butylamine / titanium tetrachloride / toluene View Scheme

pyridine-2-carboxamidrazone (1005-02-3) + 3,5-dimethyl-1,2-cyclopentanedione (13494-07-0) → C13H14N4

Conditions	Yield
In tetrahydrofuran at 66℃; for 16h;	63 %Spectr.

Upstream product

• 2687-69-6 3,5-dimethyl-cyclopent-3-ene-1,2-dione 
• 10088-87-6 4,5-dioxo-cyclopentane-1,3-dicarboxylic acid diethyl ester 
• 74-88-4 methyl iodide 

Downstream Products

• 1210405-77-8 2,(2,6-diisopropylphenylamino)-3,5-dimethylcyclopent-2-enone 
• 1135922-51-8 3-(4-chlorobenzyl)-6,8-dimethyl-1-propyl-7,8-dihydro-1H-cyclopenta[g]pteridine-2,4(3H,6H)-dione 
• 110874-92-5 2,4-dimethyl-4-<(dimethylcarbamoyl)thio>-2-cyclopenten-1-one 

Relevant articles and documents

The synthesis of some cyclic diketones isolated from coffee.

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