431-03-8

Basic information

• Product Name: 2,3-Butanedione
• Synonyms: 2,3-Butanedione 2,3-Diketobutane Dimethylglyoxal;2,3-Butanedione 97%;Two2,3-butylketone;2, 3 - butyl diketone;2,3-DIOXOBUTANE;2,3-DIKETOBUTANE;2,3-BUTANEDIONE;2,3-BUTADIONE
• CAS NO: 431-03-8
• Molecular Formula: C₄H₆O₂
• Molecular Weight: 86.09
• EINECS: 207-069-8
• Product Categories: Ketones;Organic Building Blocks;Organics;Biochemistry;Reagents for Oligosaccharide Synthesis;ketone Flavor;B;Bioactive Small Molecules;Building Blocks;C3 to C6;Carbonyl Compounds;Cell Biology;Chemical Synthesis
• Mol File: 431-03-8.mol

Chemical Properties

• Melting Point: -4--2 °C
• Boiling Point: 88 °C(lit.)
• Flash Point: 45 °F
• Appearance: Clear yellow/Liquid
• Density: 0.985 g/mL at 20 °C
• Vapor Density: 3 (vs air)
• Vapor Pressure: 52.2 mm Hg ( 20 °C)
• Refractive Index: n20/D 1.394(lit.)
• Storage Temp.: 2-8°C
• Solubility: 200g/l
• Explosive Limit: 2.4-13.0%(V)
• Water Solubility: 200 g/L (20 ºC)
• Stability: Stable. Flammable. Incompatible with acids, strong bases, metals, reducing agents, oxidizing agents. Protect from moisture and w
• Merck: 14,2966
• BRN: 605398
• CAS DataBase Reference: 2,3-Butanedione(CAS DataBase Reference)
• NIST Chemistry Reference: 2,3-Butanedione(431-03-8)
• EPA Substance Registry System: 2,3-Butanedione(431-03-8)

Safety Data

• Hazard Codes: F,Xn
• Statements: 11-20/22-38-41-36/38-20/21/22-37/38
• Safety Statements: 9-16-26-37/39-36/37/39-39
• RIDADR: UN 2346 3/PG 2
• WGK Germany: 2
• RTECS: EK2625000
• F: 13
• TSCA: Yes
• HazardClass: 3
• PackingGroup: II
• Hazardous Substances Data: 431-03-8(Hazardous Substances Data)

Usage

Uses

Used in Food Industry:
2,3-Butanedione is used as a flavoring agent for imparting a buttery flavor to various food products. It is used in the preparation of food essences like cream, cheese fermentation, and coffee-type essences. It is also used in milk, butter, margarine, cheese, sweets, and other flavors such as berry, caramel, chocolate, coffee, cherry, vanilla bean, honey, cocoa, fruit, wine, aroma, rum, nuts, almonds, ginger, and more.
Used in Cosmetic Industry:
2,3-Butanedione is used as a fresh fruit fragrance essence in makeup or new types of essences in trace amounts.
Used in Gelatin Hardening:
2,3-Butanedione serves as a gelatin hardening agent in the production of certain products.
Used in Photographic Adhesives:
2,3-Butanedione functions as a photographic adhesive agent, contributing to the bonding process in photographic materials.
Used in Enzyme Inactivation:
2,3-Butanedione is used to inactivate aminopeptidase-N, which is a precursor to α-diones.
Used in Chemical Synthesis:
2,3-Butanedione is utilized in cyclocondensation with amines to form triazine and pteridine ring systems, which are important in various chemical applications.

Content analysis

The content of 2,3-Butanedione is analyzed according to method 1(hydroxylamine method) of the aldehyde and ketone analyzing methods (OT-7). The sample weight is 500mg. The equivalent factor (e) in calculation is 21.52 .It is Fit to be analyzed using nonpolar column in GT-10-4.

Toxicity

Not specified by ADI (FAO/WHO，1994) GRAS(FEMA；FDA，§184．1278，2000)

Quantity restrictions

FEMA(mg/kg)： FEMA(mg/kg)：soft drinks 2.5；cold drinks 5.9；sweets 21；bakery products44； puddings 19；chewing gum 35；shortening 11.

Production

In nature, Diacetyl exists widely in many Plant essential oils, such as iris oil, angelica oil, laurel oil, etc. It is the main component of butter and other natural products fragrance. In industry, methyl ethyl ketone was treated with nitrite acid to generate diacetylmonoxime. Diacetylmonoxime is then decomposed by sulfuric acid to produce Butanedione. Diacetyl can be obtained by chemical ionization method from high content of essential oil. Two parts of phosphoric acid were added to one part of essential oil to produce crystalline adduct CH3CO-COCH3. Butanedione was released after the addition of water. Excessive addition of phosphoric acid will lead to liquid adduct product. Diacetyl can be obtained by special fermentation of glucose. Diacetyl can be synthesized using methyl ethyl ketone as raw material. Diacetyl was oxidized by sodium nitrite in the presence of hydrochloric acid, Then, the process of istillation is carried out after hydrolysis in the presence of sulfuric acid to produce Butanedione.

Preparation

From methyl ethyl ketone by converting to the isonitroso compound and then decomposing to diacetyl by hydrolysis with HCl; by fermentation of glucose via methyl acetyl carbinol.

Air & Water Reactions

Highly flammable. Soluble in water.

Reactivity Profile

2,3-Butanedione is a flammable liquid, b.p. 88° C, moderately toxic. When heated to decomposition 2,3-Butanedione emits acrid smoke and fumes [Sax, 9th ed., 1996, p. 544].

Health Hazard

Inhalation or contact with material may irritate or burn skin and eyes. Fire may produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or suffocation. Runoff from fire control may cause pollution.

Fire Hazard

HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids are lighter than water.

Toxicology

Diacetyl is an intensely yellowish or greenish-yellow mobile liquid. It has a very powerful and diffusive, pungent, buttery odor and typically used in flavor compositions, including butter, milk, cream, and cheese. Diacetyl was found to be mutagenic in Ames test conducted under various different conditions with Salmonella typhimurium strains. For example, diacetyl was mutagenic by TA100 in the absence of S9 metabolic activation at doses up to 40 mM/plate. It was mutagenic in a modified Ames assay in Salmonella typhimurium strains TA100 with and without S9 activation. The acute oral LD50 of diacetyl in guinea pigs was calculated to be 990 mg/kg. The acute oral LD50 of diacetyl in male rats was calculated to be 3400 mg/kg, and in female rats, the LD50 was calculated to be 3000 mg/kg. When male and female rats were administered via gavage a daily dose of 1, 30, 90, or 540 mg/kg/day of diacetyl in water for 90 days, the high-dose produced anemia, decreased weight gain, increased water consumption, increased leukocyte count, and an increase in the relative weights of liver, kidneys, and adrenal and pituitary glands. The data for teratogenicity and carcinogenicity are not available. Although the FDA has affirmed diacetyl GRAS as a flavoring agent, low molecular weight carbonyls, such as formaldehyde, acetaldehyde, and glyoxal have been reported to possess a certain chronic toxicity.

Safety Profile

A poison by ingestion and intraperitoneal routes. A skin irritant. Human inhalation hazard in popcorn manufacture. Human mutation data reported. Flammable liquid. Dangerous fire hazard when exposed to heat or flame. To fight fire, use alcohol foam, CO2, dry chemical. When heated to decomposition it emits acrid smoke and fumes. See also KETONES.

Carcinogenicity

Diacetyl was tested for its ability to induce primary lung tumors in strain A/He mice. The mice received three IP injections of diacetyl per week for 8 weeks and were killed 24 weeks after the first injection. The total dose of diacetyl given was 1.7 or 8.4 g/kg. The number of lung tumors in diacetyl exposed mice was not significantly different from the control mice.Inhalation carcinogenicity bioassays withWistar Han rats and B6C3F1 mice at exposure levels of 0, 12.5, 25, and 50 ppm are underway according to the National Toxicology Program.

Environmental Fate

Mechanisms of diacetyl-induced toxicity are not known, but some possible mechanisms of toxicity have been postulated. The adjacent carbonyl groups on diacetyl make it a reactive compound. In vitro studies have demonstrated that diacetyl can bind to arginine and inactivate proteins. The electron affinity of diacetyl suggests that it can undergo electron transfer activity, which can lead to oxidative stress by oxygen redox cycling. Redox cycling and oxidative stress may also be initiated during metabolism of diacetyl by DCXR (dicarbonyl/L-xylulose reductase). Reactive oxygen species are known to be produced from metabolic activation of dicarbonyl substrates by related carbonyl reductase enzymes in the presence of O2.

Purification Methods

Dry biacetyl over anhydrous CaSO4, CaCl2 or MgSO4, then distil it in a vacuum under nitrogen, taking the middle fraction and storing it at Dry-Ice temperature in the dark (to prevent polymerization). [Beilstein 1 IV 3644.]

Toxicity evaluation

Diacetyl released to the environment is expected to be highly mobile in soil and is not expected to adsorb to suspended sediments and solids in water. Diacetyl is degraded by a bacterium tentatively identified as Pseudomonas. Bioconcentration of diacetyl by aquatic organisms is not likely. Diacetyl is expected to volatilize from soil and water surfaces, and diacetyl is likely to exist solely as a vapor in the ambient atmosphere. In the atmosphere, diacetyl is degraded by photochemically produced hydroxyl radicals and it undergoes photolysis.

InChI:InChI=1/C4H6O2/c1-3(5)4(2)6/h1-2H3

Upstream product

• 186581-53-3 diazomethane 
• 60-29-7 diethyl ether 
• 131543-46-9 Glyoxal 
• 78-98-8 2-oxopropanal 
• 4401-11-0 1-oxiranyl-ethanone 
• 689-97-4 3-buten-1-yne 
• 609-14-3 2-acetylpropanoic acid ethyl ester 
• 31329-64-3 3,5-dimethylisoxazol-4-amine 
• 56-23-5 tetrachloromethane 
• 107-01-7 butene-2 
• 509-14-8 tetranitromethane 
• 4461-41-0 2-chloro-but-2-ene 
• 18216-47-2 2,3-dicyano-2,3-butanediol 
• 5328-37-0 L-arabinose 

Downstream Products

• 92152-08-4 (1E,5E)-1,6-di(furan-2-yl)hexa-1,5-diene-3,4-dione 
• 7154-32-7 dimethyl-2,3 pyrido<2,3-b>pyrazine 
• 16042-70-9 butane-2,3-dione bis(2′-pyridylhydrazone) 
• 6499-39-4 2,3-Dimethyl-1,4,5,8-tetraaza-naphthalin 
• 704-61-0 6,7-dimethyl-pteridine 
• 23767-00-2 2,6,7-Trimethyl-pteridin 
• 80623-34-3 2,3-butanedione bisisonicotinoylhydrazone 
• 109868-80-6 2,3-dimethyl-pyrido[3,4-b]pyrazin-8-ylamine 
• 6479-03-4 2,3,6,7-Tetramethyl-1,4,5,8-tetra-azanaphthalin 
• 68884-02-6 3-amino-5,6-dimethyl-pyrazine-2-carboxylic acid amide 
• 89977-50-4 6,7-Dimethyl-2-oxo-1,2-dihydro-pteridin 
• 34244-81-0 2,6,7-trimethylpteridin-4(3H)-one 
• 103262-24-4 6,7,8-trimethyl-8H-pteridin-4-one 
• 103262-23-3 6,7,8-Trimethyl-2-oxo-2,8-dihydro-pteridin 

Relevant articles and documents

Models for Oxygenases That Catalyze the Cleavage of Carbon-Carbon Bonds: Kinetics and Mechanism of the Decomposition of 2,3-Dimethyl-3-peroxyindolenines in Aqueous Solution

At 41 deg C in aqueous solution, 2,3-dimethyl-2-(hydroperoxy)indolenine (6) and 2,3-dimethyl-3-(methylperoxy)indolenine (7) react according to first-order kinetics to give, depending on pH, o-acetamidoacetophenone (8), 2,3-butanedione (biacetyl), or a mixture of the two in virtually quantitative yield.The pH-rate and product profiles obtained with 6 and 7 show some similarities but are not identical.With 7 as reactant the rate constant for formation of each product is characterized by a bell-shaped curve, the half-maximum points being at ca. pH 2.2 and 6 for biacetyl formation and at 6 and 7.5 for the formation of 8.Compound 6 reacts more rapidly and over a broader pH range; the overall ferst-order rate constant is at a maximum and relatively constant from pH 4 to 10, but it decreases at low and high pH.Above pH 7, 8 is the only product, but a mixture of 8 and biacetyl are formed at lower pHs.The pKas of protonated 6 and 7 were found to be 2.28 and 2.18 respectively.Studies with 18O-labeled 6 indicate that at pH 4 8 is formed with essentially 100percent of the amide group labeled, but at higher pHs, the amount of unlabeled oxygen in this position increases to a maximum of 50percent at pHs 9 to 12.6.The results with 7 can be quantitatively rationalized in terms of a mechanism that involves cis and trans isomers of a carbinolamine (formed by hydration of 7) as important intermediates.Both geometric isomers can give biacetyl through a ring-opened intermediate that undergoes a carbon to oxygen migration of the aryl group.Only one geometric isomer can give 8, apparently by rapid decomposition of the alkoxide formed from the intermediate carbinolamine.The reaction of 6 is too complex to be able to fit the data quantitatively to a particular reaction mechanism, but qualitative considerations indicate that 8 can be formed from 6 by three different mechanisms that all seem to be competing under the reaction conditions.The relevance of these findings to related enzymic reactions is briefly considered.

AZIRINYL AND DIAZIRINYL (CHLORIDE) ION PAIRS AS INTERMEDIATES

Both ab initio calculations and experimental observations support the intermediacy of diazirinyl or azirinyl cation-chloride anion pairs in transformations (1), (2), and (4).

KINETICS AND MECHANISM OF THE OXIDATION OF SOME ALIPHATIC KETONES BY N-BROMOACETAMIDE IN ACIDIC MEDIA

Kinetics of the oxidation of methyl ethyl ketone (MEK) and diethyl ketone (DEK) by N-bromoacetamide (NBA) have been studied in perchloric acid media in the presence of mercuric acetate.A zero order dependence to NBA and a first-order dependence to both ketones and H(1+) have been observed.Acetamide, mercuric acetate and sodium perchlorate additions have negligible effect while addition of acetic acid has a positive effect on the reaction rate.A solvent isotope effect (K0D2O/k0H2O=2.1-2.4 and 2.2-2.5 for MEK and DEK, respectively) has been obsvered at 40 deg C.Kinetic investigations have revealed that the order of reactivity is MEK > DEK.The rates were determined at four different temperatures and the activation parameters were evaluated.The main product of the oxidation is the corresponding 1,2-diketone.A suitable mechanizm consistent with the above observations has been proposed.

Kinetics and mechanism of the tropospheric reaction of 3-hydroxy-3-methyl- 2-butanone with Cl atoms

The relative rate coefficient for the gas-phase reaction of 3-hydroxy-3-methyl-2-butanone (3H3M2B) with Cl atoms was determined under atmospheric conditions (298 ± 2 K, 720 ± 2 Torr). The products of the reaction were identified and quantified. This work

Reaction Kitenics in Acetyl Chemistry over a Wide Range of Temperature and Pressure

The molecular modulation spectrometer has been used to study the complex chemical kitenics involed in acetyl radical chemistry.This has involved direct monitoring of both acetyl and methyl radicals in the same experiment and over a variety of temperatures (263 /1019 molecule cm-3 = 2.7) conditions.These measurements have been complemented by a non-linear least-squares analysis of the experimental data and simple product studies.Rate data on four reactions and the absorption cross-section of the acetyl radical at 223 nm have been determined in this way.Unimolecular rate theory, based on Kassel integrals, has been applied to the pressure-dependent formation and decay of the radical to extract limiting values for the rate constants at T = 303 and 343 K.

Synthesis of 2,3-butanedione over TS-1, Ti-NCl, TiMCM-41, Ti-Beta, Fe-Si, Fe-Beta and VS-1 zeolites

The purpose of this work is the synthesis of 2,3-butanedione (diacetyl) by selective oxidation of 2-butanone (methyl ethyl ketone) in the presence of O2 and H2O2 30% as oxidants. All the tests were performed over several selective oxidation zeolite catalysts, synthesized and characterized in our laboratory.

Rate coefficients for the reaction of the acetyl radical, CH3CO, with Cl2 between 253 and 384 K

Rate coefficients, k, for the gas-phase reaction CH3CO + Cl 2 → products (2) were measured between 253 and 384 K at 55-200 Torr (He). Rate coefficients were measured under pseudo-first-order conditions in CH3CO with CHsub

Synthesis of Dialkyl- and Alkylacylrhenium Complexes by Alkylation of Anionic Rhenium Complexes at the Metal Center. Mechanism of a Double Carbonylation Reaction That Proceeds via the Formation of Free Methyl Radicals in Solution

The site of alkylation of salts of acylrhenates such as Li(1+)(1-) (1) can be controlled by adjusting the hardness of the alkylating agent.Thus, treatment of 1 with the hard alkylating agent (CH3)3OPF6 gives predominantly the clssical Fischer carbene complex Cp(CO)2Re=C(OCH3)(CH3) (2), whereas reaction with the softer electrophile CH3I leads almost exclusively to the new metal-alkylated complex Cp(CO)2Re(CH3)(COCH3) (3).The structure of 3 has been determined by X-ray diffraction.The availability of this material, a relatively rare example of astable alkylacylmetal complex, has provided an opportunity to study the products and mechanisms of its carbon-carbon bond-forming decomposition reactions.Thermally, the alkyl acyl complex undergoes simple reductive elimination, leading (in the presence of a metal-scavenging ligand L) to a quantitative yield of acetone and CpRe(CO)2(L).Photochemically, a more complicated reaction takes place, especially under 20 atm of CO, where CpRe(CO)3 and 2,3-butanedione are formed.Strikingly, irradiation of Cp(CO)2Re(CH3)2 (9) under 20 atm of CO gives products identical with those formed from 3.Labeling experiments using (13)CO and mixtures of acetyl- and propionylrhenium complexes are inconsistent with a mechanism involving simple migratory CO insertion followed by reductive elimination.They are, however, consistent with metal-carbon bond homolysis leading to methyl and acetyl radicals, followed by carbonylation of the methyl radicals to give a second source of acetyl radicals; these reactive intermediates then dimerize to give 2,3-butanedione.Confirmation of this mechanism was obtained by trapping all the initially formed radicals withhalogen donors.BrCCl3, proved to be much more efficient than CCl4 for this purpose: irradiation of alkyl acyl complex 3 in the presence of BrCCl3 diverted the reaction completely from 2,3-butanedione production, giving instead CH3Br, CH3COBr, Cp(CO)2Re(CH3)Br, and Cp(CO)2Re(CH3CO)Br.

OXIDATION OF ALIPHATIC KETONES BY BROMAMINE-B: A KINETIC STUDY

The kinetics of oxidation of propan-2-one, butan-2-one, pentan-2-one, pentan-3-one and 4-methyl pentan-2-one by sodium N-bromobenzenesulphonamide or bromamine-B (BAB) in perchloric acid medium was studied at 30 deg C.The rate shows a first order dependence each on and +> and is independent of .Variation of ionic strength of medium and addition of the reaction product benzenesulphonamide have no effect on the rate and the dielectric effect is positive.The proposed mechanism involves acid catalysed enolisation of ketone in the rate limiting step followed by a fast interaction with the oxidant.This is supported by the magnitude of inverse solvent isotope effect of 1.62 +/- 0.01 observed in D2O medium.Activation parameters Ea, ΔH*, ΔS*, ΔG* and log A have been calculated by studying the reaction at different temperatures (293-309 K).

Iron complexes with nitrogen bidentate ligands as green catalysts for alcohol oxidation

The iron(II) complexes [Fe(N-N)3](OTf)2 (N-N = 2,2′- bipyridine, 1,10-phenanthroline and substituted derivatives) were employed as catalyst precursors for the oxidation of primary and secondary alcohols, including glycerol. The single-crystal structure of [Fe(bipy)3](OTf)2 was determined by X-ray crystallography.The catalytic reactions were performed using either H2O2 or tert-butilhydroperoxide (TBHP) as oxidating agent, in mild experimental conditions: with all catalysts employed, secondary alcohols were oxidized to the corresponding ketones with up to 100% yields, whereas other substrates gave lower conversions. Indications on the nature of the catalytically active species, which is probably formed via dissociation of a nitrogen ligand from the iron center, were obtained from NMR and ESI-MS spectra.