Chemical Properties
white to light yellow crystal powder
Uses
2-Acetyl-5-methylthiophene may be used in the preparation of:
- 2-ethyl-5-methylthiophene
- (5-methylthiophen-2-yl)glyoxal
- (2E)-1-(5-methylthiophen-2-yl)-3-(pyridin-3-yl)prop-2-en-1-one
- ethyl 3-(5-methylthiophen-2-yl)-3-oxopropanoate
Definition
ChEBI: 2-acetyl-5-methylthiophene is a thiophene that is substituted by acetyl and methyl groups at positions 2 and 5, respectively. It has a role as a flavouring agent. It is an aromatic ketone, a member of thiophenes and a methyl ketone.
General Description
2-Acetyl-5-methylthiophene is a volatile organic compound formed during the reaction between L-cysteine and dihydroxyacetone in glycerine or triglyceride solvent system. It can be prepared by reacting 2-methylthiophene with acetic anhydride. 2-Acetyl-5-methylthiophene undergoes palladium-catalyzed cross-coupling reaction with aryl bromides to form C-4 arylated product. It reacts with 1,2-bis(5-formyl-2-methylthiophen-3-yl)cyclopentene via Aldol condensation to form a chalcone with photochromic property. The standard molar enthalpies of combustion, formation and vaporization of 2-acetyl-5-methylthiophene are 4341.9 ± 1.8kJ/mol, 158.0 ± 2.1kJ/mol and 62.0 ± 2.6kJ/mol, respectively.
Safety Profile
A poison by
intraperitoneal route. A flammable liquid.
When heated to decomposition it emits
toxic vapors of SOx.