2758-18-1

Basic information

• Product Name: 3-Methyl-2-cyclopenten-1-one
• Synonyms: 1-Methyl-1-cyclopenten-3-one;3-methyl-2-cyclopenten-1-on;3-Methyl-cyclopent-2-enone;3-METHYL-2-CYCLOPENTEN-1-ONE FOR SYNTHES;3-Methyl-2-cyclopenten-1-one, GC 98%;3-Methyl-2-cyclopentenone 97%;3-Methyl-2-cyclopenten-1-one, 97%+;3-Methyl-2-cyclopenten-1-one, stabilised
• CAS NO: 2758-18-1
• Molecular Formula: C₆H₈O
• Molecular Weight: 96.13
• EINECS: 220-421-5
• Product Categories: Organic Building Blocks;Pyridines;ketone;C3 to C6;Carbonyl Compounds;Ketones;Building Blocks;C3 to C6;Carbonyl Compounds;Chemical Synthesis
• Mol File: 2758-18-1.mol
• Article Data: 76

Chemical Properties

• Melting Point: 3-5 °C(lit.)
• Boiling Point: 74 °C15 mm Hg(lit.)
• Flash Point: 150 °F
• Appearance: Clear light yellow to yellow-brown/Liquid
• Density: 0.971 g/mL at 25 °C(lit.)
• Vapor Pressure: 2.74mmHg at 25°C
• Refractive Index: n20/D 1.488(lit.)
• Storage Temp.: Refrigerator (+4°C)
• Water Solubility: miscible
• BRN: 1280476
• CAS DataBase Reference: 3-Methyl-2-cyclopenten-1-one(CAS DataBase Reference)
• NIST Chemistry Reference: 3-Methyl-2-cyclopenten-1-one(2758-18-1)
• EPA Substance Registry System: 3-Methyl-2-cyclopenten-1-one(2758-18-1)

Safety Data

• Statements: 36/38
• Safety Statements: 24/25
• RIDADR: 1224
• WGK Germany: 3
• TSCA: Yes
• PackingGroup: III
• Hazardous Substances Data: 2758-18-1(Hazardous Substances Data)

Usage

Description

3-Methyl-2-cyclopenten-1-one is an organic compound with the molecular formula C6H8O. It is a clear light yellow to yellow-brownish liquid, known for its sweet-floral, warm-spicy, and diffusive yet quite tenacious odor. 3-Methyl-2-cyclopenten-1-one is often prepared by the dehydrohalogenation of 2-chloro-1-methylcyclopentan-3-one and is a component of smoke flavoring. It has been reported to be found in various food items such as roasted onion, cooked pork, black tea, soybean, and dried bonito.

Uses

Used in Organic Synthesis:
3-Methyl-2-cyclopenten-1-one is used as an important raw material and intermediate in organic synthesis for the production of various compounds.
Used in Pharmaceuticals:
3-Methyl-2-cyclopenten-1-one is also utilized as a key intermediate in the pharmaceutical industry, contributing to the synthesis of different medicinal products.
Used in Agrochemicals:
3-Methyl-2-cyclopenten-1-one finds application in the agrochemical sector, serving as a vital intermediate in the development of various agrochemical products.
Used in Flavor and Fragrance Industry:
As a component of smoke flavoring, 3-Methyl-2-cyclopenten-1-one is used in the flavor and fragrance industry to add unique and desirable notes to products.
Used in the Synthesis of 2-Hydroxy-3-Methyl-2-Cyclopentenone:
3-Methyl-2-cyclopentenone is specifically used in the synthesis of 2-hydroxy-3-methyl-2-cyclopentenone, which has its own set of applications in various industries.

Preparation

By dehydrohalogenation of 2-chloro-1-methyl-cyclopentan-3-one.

Synthesis Reference(s)

Journal of the American Chemical Society, 101, p. 494, 1979 DOI: 10.1021/ja00496a044The Journal of Organic Chemistry, 55, p. 371, 1990

InChI:InChI=1/C6H8O/c1-5-2-3-6(7)4-5/h4H,2-3H2,1H3

Upstream product

• 110-13-4 2,5-hexanedione 
• 463-49-0 1,2-propanediene 
• 201230-82-2 carbon monoxide 
• 74-86-2 acetylene 
• 5296-50-4 1-methyl-4,4-dichlorocyclopentene 
• 67263-03-0 3-(dimethyl(phenyl)silyl)-3-methylcyclopentanone 
• 917-54-4 methyllithium 
• 104804-86-6 1,4-dioxa-7-methylspiro<4.4>non-7-ene 
• 88903-26-8 N-[3-Methyl-cyclopent-2-en-(Z)-ylidene]-N'-(4-nitro-phenyl)-hydrazine 
• 25937-41-1 3-hydroxy-3-methylcyclopentan-1-one 
• 2935-44-6 hexane-2,5-diol 
• 763-32-6 2-methyl-1-buten-4-ol 
• 105419-90-7 (2-Hydroxy-5-methyl-tetrahydro-furan-2-ylmethyl)-phosphonic acid diethyl ester 
• 10575-36-7 (1E,4E)-hexa-1,4-dien-3-one 

Downstream Products

• 859446-70-1 4-(α-hydroxy-benzyl)-3-methyl-cyclopent-2-enone 
• 145728-45-6 5-Methyl-1-phenyl-spiro[2.4]hept-4-ene 
• 80256-22-0 3-(dimethylphenylsilyl)-3-methyl-1-trimethylsilyloxycyclopentene 
• 114718-24-0 (2'E,3RS,S_SR_S)-3-methyl-3-<3'-<(4-methylphenyl)sulfinyl>prop-2'-enyl>cyclopentanone 
• 251346-32-4 3-methyl-3-[3-dimethyl(phenyl)silylprop-1-en-2-yl]cyclopentan-1-one 
• 6672-30-6 (R)-3-methylcyclopentanone 
• 6672-24-8 (S)-3-methylcyclopentanone 
• 64-18-6 formic acid 
• 110-15-6 succinic acid 
• 288304-55-2 bis(3-methylcyclopent-1-enyloxy)-diphenylsilane 
• 922734-82-5 phosphoric acid 3-benzyl-3-methyl-cyclopent-1-enyl ester diethyl ester 
• 114790-84-0 C₃₅H₃₈O₅S 

Relevant articles and documents

Vapor-phase intramolecular aldol condensation of 2,5-hexanedione to 3-methylcyclopent-2-enone over ZrO2-supported Li2O catalyst

Vapor-phase intramolecular aldol condensation of 2,5-hexanedione to produce 3-methylcyclopent-2-enone was performed over several ZrO2-supported alkali and alkali earth metal oxides. Among the tested catalysts, ZrO2-supported Li2O showed a stable catalytic activity. A high 2,5-hexanedione conversion of 99% with a 3-methylcyclopent-2-enone selectivity of 96% was achieved over a 20?mol% Li2O-loaded ZrO2catalyst at 250?°C.

Synthesis of Bio-Based Methylcyclopentadiene from 2,5-Hexanedione: A Sustainable Route to High Energy Density Jet Fuels

The sustainable, bio-based, platform chemical, 2,5-hexanedione [HD (1)], was efficiently converted to methylcyclopentadiene [MCPD (4)] through a three-step process consisting of intramolecular aldol condensation, catalytic chemoselective hydrogenation, and dehydration. Base-catalyzed aldol condensation of 1 resulted in the formation of 3-methyl-2-cyclopenten-1-one [MCO (2)], which was then converted to 3-methyl-2-cyclopenten-1-ol [MCP (3)] by chemoselective reduction with a ternary Ru catalyst system [RuCl2(PPh3)3/NH2(CH2)2NH2/KOH]. The hydrogenation proceeded with 96 % chemoselectivity. 3 was then dehydrated over AlPO4/MgSO4 at 70 °C under reduced pressure to yield 4, which can undergo an ambient temperature [4+2]-Diels-Alder cyclization to generate dimethyldicyclopentadiene (DMDCPD), a commodity chemical useful for the preparation of high-performance fuels and polymers. Through this approach, advanced jet fuels and materials can be conveniently produced from sustainable cellulosic feedstocks.

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Calcium and nitrogen species loaded into SBA-15-a promising catalyst tested in Knoevenagel condensation

Mesoporous silica of the SBA-15 type was used as a support for basic active centers generated by the incorporation of calcium species and (3-aminopropylo)trimethoxysilane (APTMS) or imidazole. The samples were characterized by low temperature N2 adsorption/desorption, XRD, XPS, FTIR spectroscopy, CO2-TPD, and elemental and thermal analyses. Calcium containing samples were analysed in 2,5-hexanedione dehydration and cyclization, while the activities of all the samples were examined in Knoevenagel condensation between benzaldehyde and malononitrile. It was demonstrated that the calcium species interacted with a silica support increasing the stabilization of organosilanes on the SBA-15 surface. A very high activity of the catalysts in Knoevenagel condensation indicated a synergistic interaction between calcium and the organic modifiers.

Transformation of γ-ketoaldehyde acetals into 3-substituted-2-cyclopentenones via cyanophosphates under mild conditions

The reaction of cyanophosphates, which are readily derived from γ-ketoaldehyde acetals, with TMSN3 (3 eq)/Bu2SnO (0.3 eq) in refluxing toluene directly furnished 3-substituted-2-cyclopentenones in modest to good yield under mild conditions. The present method was further applied toward the synthesis of dechlorotrichodenone C isolated from Trichoderma asperellum.

Preparation method of 3-methyl-2-cyclopentene-1-one

The invention provides a preparation method of 3-methyl-2-cyclopentene-1-one. A device comprises a coiled tube type reactor and two plunger pumps, the output ends of the plunger pumps are connected with the coiled tube type reactor, and the coiled tube type reactor is placed in an oil bath pan at 120-130 DEG C. The preparation method comprises the following steps: S1, preparing a 2, 5-hexanedioneaqueous solution and a 20% sodium hydroxide solution; S2, respectively immersing the plunger pumps into the 2, 5-hexanedione aqueous solution and the 20% sodium hydroxide solution, and setting the flow rate to be 10-18 mL/min; and S3, placing a 1 L four-necked bottle at the outlet of the reactor, cooling with heat-conducting oil at the temperature of 0-5 DEG C in an external bath, stopping the reaction and sampling after receiving the reaction liquid for 30 minutes, extracting with acetic acid, and carrying out GC analysis. According to the invention, a continuous reaction technology is adopted, and the reaction selectivity is regulated by adjusting the molar ratio, the feeding rate and the residence time of materials; and the reaction solution is collected and cooled after the reaction isfinished, thereby avoiding the quick decomposition of the product in the hot alkali liquor. Water is used as a solvent, and reaction is carried out at a low temperature, so environmental pollution isreduced, and energy consumption is reduced. And the yield of the prepared 3-methyl-2-cyclopentene-1-one reaches 70-75%.