Isovaleric acid Property

Melting point:

-29 °C (lit.)

Boiling point:

175-177 °C (lit.)

Density 

0.925 g/mL at 20 °C (lit.)

vapor pressure 

0.38 mm Hg ( 20 °C)

refractive index 

n20/D 1.403(lit.)

FEMA 

3102 | ISOVALERIC ACID

Flash point:

159 °F

storage temp. 

Store below +30°C.

solubility 

48g/l

form 

Liquid

pka

4.77(at 25℃)

color 

Clear colorless to slightly yellow

Specific Gravity

0.928 (20/20℃)

Odor

at 1.00 % in propylene glycol. sour stinky feet sweaty cheese tropical

PH

3.92(1 mM solution);3.4(10 mM solution);2.89(100 mM solution);

explosive limit

1.5-6.8%(V)

Odor Type

cheesy

Water Solubility 

25 g/L (20 ºC)

Merck 

14,5231

JECFA Number

259

BRN 

1098522

Dielectric constant

2.6（20℃）

LogP

1.7 at 25℃

CAS DataBase Reference

503-74-2(CAS DataBase Reference)

NIST Chemistry Reference

Butanoic acid, 3-methyl-(503-74-2)

EPA Substance Registry System

Isovaleric acid (503-74-2)

Safety

Hazard Codes 

C,T

Risk Statements 

34-24-22

Safety Statements 

26-36/37/39-45-38-28A

RIDADR 

UN 3265 8/PG 2

WGK Germany 

1

RTECS 

NY1400000

F 

13

Autoignition Temperature

824 °F

TSCA 

Yes

HS Code 

2915 60 90

HazardClass 

6.1

PackingGroup 

III

Hazardous Substances Data

503-74-2(Hazardous Substances Data)

Toxicity

LD50 i.v. in mice: 1120±30 mg/kg (Or, Wretlind)

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H314Causes severe skin burns and eye damage

Precautionary statements

P280Wear protective gloves/protective clothing/eye protection/face protection.

P301+P330+P331IF SWALLOWED: Rinse mouth. Do NOT induce vomiting.

P303+P361+P353IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P363Wash contaminated clothing before reuse.

Isovaleric acid Chemical Properties,Usage,Production

Description

Isovaleric acid has a characteristic disagreeable odor. It is extremely penetrating and persistent with a sour taste. May be synthesized by oxidation of isoamyl alcohol or isovaleric aldehyde.

Chemical Properties

Isovaleric acid has a characteristic disagreeable, rancid, cheese-like odor. It is extremely penetrating and persistent with a sour taste. May consist of one or a mixture of isomers or n-pentanoic acid and/or 2- or 3-methyl butanoic acid. Consumption: Annual: 1850.00 lb

Chemical Properties

clear colorless to slightly yellow liquid

Occurrence

Of the three possible isomers of n-valeric acid, only isovaleric acid has extensive application in flavoring; originally reported in seal and dolphin fat; subsequently isolated from valerian. Also reported found in the essential oils of cypress, citronella, laurel leaves, cajeput, Cymbopogon javanensis, hops, Persea pubescens, geranium, American peppermint, spearmint, rosemary, lemongrass, Eucalyptus goniocalyx and other spp., tobacco, Monarda fistulos, Thymus mastichina, Artemisia frigida, and probably in lavender; reported among the constituents of petitgrain lemon. Also reported found in many foods including apple, currants, guava, grapes, papaya, peach, pineapple, raspberry, strawberry, potato, bell pepper, vinegar, breads, many cheeses, fish, chicken, lamb, hop oil, beer, cognac, whiskies, cider, sherry, grape wines, rum, cocoa, tea, coffee, honey, soybean, passion fruit, mushrooms, marjoram, plum, brandy, starfruit, trassi, rice, jackfruit, sake, sukiyaki, buckwheat, corn oil, cashew apple, malt, wort, Bourbon vanilla, shrimp, mussels, cherimoya, Cape gooseberry and Chinese quince frui

Uses

Isovaleric acid is used extensively as a flavoring ingredient in nonalcoholic beverages and in foods such as ice cream, candy, baked goods, and cheese, as a fragrance ingredient in perfumes, and as a chemical intermediate in the manufacture of sedatives and other pharmaceutical products. It is also used as an extractant of mercaptans from petroleum hydrocarbons, a vinyl stabilizer, and as an intermediate in the manufacture of plasticizers and synthetic lubricants.

Uses

A molecular entity capable of donating a hydron to an acceptor (Bronsted base). It is a favorable carbon source for cell growth. Moreover, it is a promising odor indicator.

Uses

In flavors, perfumes, manufacture of sedatives.

Preparation

By oxidation of isoamyl alcohol or isovaleric aldehyde

Definition

ChEBI: A C5, branched-chain saturated fatty acid.

Aroma threshold values

Detection: 190 ppb to 2.8 ppm

Synthesis Reference(s)

Chemical and Pharmaceutical Bulletin, 30, p. 2787, 1982 DOI: 10.1248/cpb.30.2787
Tetrahedron Letters, 23, p. 3135, 1982 DOI: 10.1016/S0040-4039(00)88578-0

General Description

Isovaleric acid is a colorless liquid with a penetrating odor. Isovaleric acid is slightly soluble in water. Isovaleric acid is corrosive to metals and to tissue.

Air & Water Reactions

Isovaleric acid is slightly soluble in water.

Reactivity Profile

Isovaleric acid is a carboxylic acid. Carboxylic acids donate hydrogen ions if a base is present to accept them. They react in this way with all bases, both organic (for example, the amines) and inorganic. Their reactions with bases, called "neutralizations", are accompanied by the evolution of substantial amounts of heat. Neutralization between an acid and a base produces water plus a salt. Carboxylic acids with six or fewer carbon atoms are freely or moderately soluble in water; those with more than six carbons are slightly soluble in water. Soluble carboxylic acid dissociate to an extent in water to yield hydrogen ions. The pH of solutions of carboxylic acids is therefore less than 7.0. Many insoluble carboxylic acids react rapidly with aqueous solutions containing a chemical base and dissolve as the neutralization generates a soluble salt. Carboxylic acids in aqueous solution and liquid or molten carboxylic acids can react with active metals to form gaseous hydrogen and a metal salt. Such reactions occur in principle for solid carboxylic acids as well, but are slow if the solid acid remains dry. Even "insoluble" carboxylic acids may absorb enough water from the air and dissolve sufficiently in Isovaleric acid to corrode or dissolve iron, steel, and aluminum parts and containers. Carboxylic acids, like other acids, react with cyanide salts to generate gaseous hydrogen cyanide. The reaction is slower for dry, solid carboxylic acids. Insoluble carboxylic acids react with solutions of cyanides to cause the release of gaseous hydrogen cyanide. Flammable and/or toxic gases and heat are generated by the reaction of carboxylic acids with diazo compounds, dithiocarbamates, isocyanates, mercaptans, nitrides, and sulfides. Carboxylic acids, especially in aqueous solution, also react with sulfites, nitrites, thiosulfates (to give H2S and SO3), dithionites (SO2), to generate flammable and/or toxic gases and heat. Their reaction with carbonates and bicarbonates generates a harmless gas (carbon dioxide) but still heat. Like other organic compounds, carboxylic acids can be oxidized by strong oxidizing agents and reduced by strong reducing agents. These reactions generate heat. A wide variety of products is possible. Like other acids, carboxylic acids may initiate polymerization reactions; like other acids, they often catalyze (increase the rate of) chemical reactions.

Hazard

Strong irritant to tissue.

Health Hazard

TOXIC; inhalation, ingestion or skin contact with material may cause severe injury or death. Contact with molten substance may cause severe burns to skin and eyes. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution.

Fire Hazard

Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated.