2,3-butanedione CAS 431-03-8 basic information

2,3-butanedione CAS 431-03-8 basic information

Butanedione - Basic information

Diacetyl (2,3-butanedione, C4H6O2) at room temperature is light yellow to yellowish-green liquid with benzoquinone odor, dilute solution with cream odor, present in fennel oil and cream. Soluble in water, can be miscible with ethanol, ether. Mainly used as cream, margarine, cheese and confectionery flavor enhancer, gelatin hardener, etc.

The basic information

Chinese name

diacetyl

Chemical formula

CH3CO-COCH3

Flash point

13 ℃

Melting point

- 3 ~ 4 ℃

Symbol of danger

F, Xn

Outside view

Light yellow to yellowish-green liquid with a creamy odour in dilute solutions

Don't say

Diacetylone, 2, 3-butanedione

The molecular weight

86.09

Should be used

One of the important components in liquor, used in feed essence

Dense degree of

0.990 g/cm3

The English name

2, 3 - butanedione

Boiling point

88 ~ 91 ℃

Water soluble

Soluble in water

Dangerous goods Transport Number

The UN 2346 3 / PG 2

Chinese name 2, 3-butanedione

2, 3 - Butanedione English name

Diacetyl of another name

butanedione

2, 3-butane diketone

English alias DIACETYLE

Biacetyl

Diacetyl

Butane - 2, 3 - dione

CAS 431-03-8

EINECS 207-069-8

Chemical formula C4H6O2

The molecular weight of 86.0892

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

The density of 0.969 g/cm3

Melting point - 4 ℃

Boiling point 88°C at 760 mmHg

Flash point 5.5 ° C

Water soluble 200 g/L (20℃)

Vapor pressure 62.3mmHg at 25°C

The refractive index of 1.381

Physical and chemical density 0.981

The boiling point of 88 ° C

The refractive index of 1.391 to 1.399

Flash point 7 ° C

Water soluble 200 g/L (20°C)

It is the main raw material for producing pyrazine flavor

Dangerous Goods Mark F - Flammable goods

Xn - Hazardous substances

Risk Term R11 - Highly flammable.

R20/21/22 - Harmful by inhalation, in contact with skin and if swallowed.

R36/38 - Irritates eyes and skin.

Safety Term S16 - Keep away from ignition.

S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice.

S36/37/39 - Wear appropriate protective clothing, gloves and goggles or masks.

Dangerous goods Transport Code UN 2346

Upstream raw material 2-butanone sulfuric acid sodium nitrite sulfate ethanol

The synthetic methods

1. In nature, butaneone is widely found in essential oils of various plants, such as iris oil, angelica oil and bay oil, etc. It is the main component of the fragrance of butter and some other natural products. Industrial production of butanedione is methyl ethyl ketone with nitrite treatment, to produce butanedione oxime, and then with dilute sulfuric acid decomposition. Or with vinyl acetylene or methyl vinyl ketone through hydration reoxidation method. The laboratory can use selenium dioxide oxidation butanone preparation, also useful diketone dioxime and sodium nitrite reaction method.

2. It can be obtained by free method from the essential oil with high content: 1 part essential oil is added with 2 parts phosphoric acid to generate crystalline admixture C4H6O2·2H3PO4. After adding water, butanedione will be released. It is obtained by special fermentation of glucose. It was synthesized with methyl ethyl ketone as the starting material. It is obtained by oxidation of butanone with sodium nitrite in the presence of hydrochloric acid, hydrolysis with sulfuric acid and distillation.

Tobacco: OR, 18; 3. FC, 40.

4. Method:

Add 40g (0.56mol) of 2-butanone (2) and 52mL concentrated hydrochloric acid to the reaction flask equipped with agitator, thermometer, reflux condenser and drip funnel (lower end extending below the liquid level), then drop 40g (0.58mol) of sodium nitrite dissolved in 136mL water at 50 ~ 60℃ under fierce stirring, and add the solution for about 2h. Notice the nitric oxide escaping. After adding, transfer the reactants to a 5L reaction flask, add 141g sodium nitrite solution dissolved in 240mL water, and condense it with air. Drop 120mL concentrated sulfuric acid and 340mL water solution from the top of the condenser, and finish adding in 10min. The mixture was left for 2 days until the nitrous acid disappeared (can be tested with potassium iodide-starch dipstick). Add 200g sodium sulfate and distill. The distillation was stopped when the sample of distillate solution mixed with 20% sodium hydroxide solution did not become turbid. The distillate was dried with anhydrous sodium sulfate, redistilled, and fractions at 86 to 88 ° C were collected. The crude product obtained in this way was dried with anhydrous sodium sulfate, distilled, and collected at 86 ~ 88℃ to obtain 16 ~ 18g of 2, 3-butanedione (1), with a yield of 33.3% ~ 37.5%. [1]

The main purpose

1. It is mainly used for preparing food flavor, is the main flavor of cream flavor, can also be used in milk, cheese and some other fragrances. Such as berries, caramel, chocolate, coffee, cherries, vanilla beans, honey, cocoa, fruit, wine, tobacco, rum, nuts, almonds, ginger and so on. Can also be used in a small amount of cosmetics with fresh fruit fragrance or new flavor. Used as solvent, organic synthesis intermediate. 2. Can also be used as a hardener for gelatin. It is an important reagent to identify nickel.