533610

2-Acetyl-5-methylthiophene

98%

• Synonym(s): 1-(5-Methyl-2-thienyl)ethanone, 1-(5-Methylthiophen-2-yl)ethan-1-one, 1-(5-Methylthiophen-2-yl)ethanone, 2-Methyl-5-acetylthiophene, 5-Methyl-2-thienyl methyl ketone, Methyl 5-methyl-2-thienyl ketone
• Empirical Formula (Hill Notation): C₇H₈OS
• CAS Number: 13679-74-8
• Molecular Weight: 140.20
• EC Number: 237-181-2
• MDL number: MFCD00014529
• UNSPSC Code: 12352100
• PubChem Substance ID: 24877976
• NACRES: NA.22

Properties

• assay: 98%
• refractive index: n20/D 1.561 (lit.)
• bp: 65-67 °C/1 mmHg (lit.)
• mp: 24-28 °C (lit.)
• density: 1.106 g/mL at 25 °C (lit.)
• SMILES string: CC(=O)c1ccc(C)s1
• InChI: 1S/C7H8OS/c1-5-3-4-7(9-5)6(2)8/h3-4H,1-2H3
• InChI key: YOSDTJYMDAEEAZ-UHFFFAOYSA-N

Description

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.

Application

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

Safety Information

• Storage Class: 11 - Combustible Solids
• wgk_germany: WGK 3
• flash_point_f: Not applicable
• flash_point_c: Not applicable
• ppe: Eyeshields, Gloves, type N95 (US)