Trimethyl-pyrazine Property

Melting point:

156 °C

Boiling point:

171-172 °C (lit.)

Density 

0.979 g/mL at 25 °C (lit.)

refractive index 

n20/D 1.5040(lit.)

FEMA 

3244 | 2,3,5-TRIMETHYLPYRAZINE

Flash point:

130 °F

storage temp. 

Inert atmosphere,Room Temperature

solubility 

Chloroform (Slightly)

pka

2.69±0.10(Predicted)

form 

Liquid

color 

Colorless to Light yellow to Light orange

Specific Gravity

0.979

Odor

roasted odor, reminiscent of coffee and cocoa

Odor Type

nutty

JECFA Number

774

BRN 

2423

InChIKey

IAEGWXHKWJGQAZ-UHFFFAOYSA-N

LogP

1.10

CAS DataBase Reference

14667-55-1(CAS DataBase Reference)

NIST Chemistry Reference

Pyrazine, trimethyl-(14667-55-1)

EPA Substance Registry System

Trimethylpyrazine (14667-55-1)

Safety

Hazard Codes 

Xn

Risk Statements 

10-22-36/37/38

Safety Statements 

16-26-36/37/39

RIDADR 

UN 1993 3/PG 3

WGK Germany 

3

RTECS 

UQ3907000

TSCA 

Yes

HazardClass 

3

PackingGroup 

III

HS Code 

29339900

Toxicity

rat,LD50,oral,806mg/kg (806mg/kg),Drug and Chemical Toxicology. Vol. 3, Pg. 249, 1980.

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H226Flammable liquid and vapour

H302Harmful if swallowed

H315Causes skin irritation

H319Causes serious eye irritation

H335May cause respiratory irritation

Precautionary statements

P210Keep away from heat/sparks/open flames/hot surfaces. — No smoking.

P302+P352IF ON SKIN: wash with plenty of soap and water.

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

Trimethyl-pyrazine Chemical Properties,Usage,Production

Chemical Properties

CLEAR YELLOW LIQUID

Chemical Properties

2,3,5-Trimethylpyrazine has a baked potato or roasted nut aroma.

Occurrence

Reported present in bakery products, roasted barley, cocoa products, coffee, dairy products, meat, peanuts, filberts, pecans, popcorn, potato products, rum and whiskey, soy products, raw asparagus, baked potato, wheaten bread, crispbread, Swiss cheese, coffee, black tea, green tea, roasted barley, roasted filbert, heated beef, roasted peanut, soybean, raw beans, coriander seed, scallop, guava, kohlrabi, bell pepper, blue, Swiss and Gruyere cheese, boiled egg, fatty fish, beer, sherry, barley, peanut, oat products, coconut, beans, mushroom, trassi, almond, macadamia nut, sesame seed, coriander seed, rice, licorice, sweet corn, malt, peated malt, wort, krill, fermented shrimp, crab, okra, crayfish, clam, scallop and squid.

Uses

Trimethylpyrazine is a key aroma compound of dark chocolates differing in organoleptic properties.

Uses

2,3,5-Trimethylpyrazine can be used as a flavor ingredient in food industries.

Definition

ChEBI: Trimethylpyrazine is a member of the class of pyrazines that is pyrazine in which three hydrogens at positions 2, 3 and 5 have been replaced by methyl groups. It has a role as a plant metabolite, a flavouring agent, a bacterial metabolite, an animal metabolite and a pheromone.

Preparation

From 2,5-dimethylpyrazine by ring alkylation with MeLi; by condensing propylenediamine with 2,3-butanedione.

Aroma threshold values

Detection: 400 ppb to 9 ppm (9 ppm in water)

Taste threshold values

Taste characteristics at 80 ppm: raw, musty, nutty and potato.

General Description

2,3,5-Trimethylpyrazine is present in brown cheese.

Safety Profile

Moderately toxic by ingestion. Combustible liquid. When heated to decomposition emits toxic fumes of NOx.