30319-05-2

Basic information

• Product Name: 3-bromo-2-methylthiophene
• Synonyms: 3-bromo-2-methylthiophene;2-Methyl-3-bromothiophene;Einecs 250-128-8
• CAS NO: 30319-05-2
• Molecular Formula: C₅H₅BrS
• Molecular Weight: 177.0622
• EINECS: 250-128-8
• Product Categories: Thiophens
• Mol File: 30319-05-2.mol
• Article Data: 19

Chemical Properties

• Boiling Point: 179 °C at 760 mmHg
• Flash Point: 62 °C
• Appearance: /
• Density: 1.589 g/cm³
• Vapor Pressure: 1.3mmHg at 25°C
• Refractive Index: 1.581
• Storage Temp.: Refrigerated.
• CAS DataBase Reference: 3-bromo-2-methylthiophene(CAS DataBase Reference)
• NIST Chemistry Reference: 3-bromo-2-methylthiophene(30319-05-2)
• EPA Substance Registry System: 3-bromo-2-methylthiophene(30319-05-2)

Safety Data

• Hazard Codes: Xi
• Hazardous Substances Data: 30319-05-2(Hazardous Substances Data)

Usage

General Description

3-bromo-2-methylthiophene is a chemical compound with the molecular formula C5H5BrS. It is a brominated derivative of 2-methylthiophene, which is a heterocyclic compound containing a sulfur atom in its five-membered ring. 3-bromo-2-methylthiophene is a colorless to pale yellow liquid that is primarily used as an intermediate in the synthesis of pharmaceuticals and agrochemicals. It is also used in the production of polymers and as a building block in organic synthesis. The bromine substituent on the thiophene ring makes this compound reactive and versatile for various chemical reactions and applications in the pharmaceutical and chemical industries.

InChI:InChI=1/C5H5BrS/c1-4-5(6)2-3-7-4/h2-3H,1H3

Upstream product

• 29421-73-6 3,5-dibromo-2-methylthiophene 
• 554-14-3 2-Methylthiophene 
• 19162-82-4 (3-bromo-2-thienyl)lithium 
• 80-18-2 Methyl benzenesulfonate 
• 872-31-1 3-Bromothiophene 
• 74-88-4 methyl iodide 
• 109-99-9 tetrahydrofuran 

Downstream Products

• 16494-34-1 3-iodo-2-methylthiophene 
• 1918-78-1 2-methylthiophene-3-carboxylic acid 
• 95184-19-3 2-methyl-3-(2-methyl-1,3-diphenylcyclopropen-3-yl)thiophene 
• 95184-11-5 2-methyl-3-(3-methyl-1,2-diphenylcyclopropen-3-yl)thiophene 
• 95184-12-6 2-methyl-4-(3-methyl-1,2-diphenylcyclopropen-3-yl)thiophene 
• 2527-76-6 2-methylthiophene-3-thiol 
• 84815-20-3 2-methyl-3-thiophenecarboxaldehyde 
• 345306-46-9 2-methyl-3-(2-methylphenyl)thiophene 
• 345306-56-1 3-(2,5-dimethyl-phenyl)-2-methyl-thiophene 
• 16939-16-5 2-methyl-3-phenylthiophene 
• 868134-75-2 (4-bromo-5-methyl-thiophen-2-yl)-phenyl-methanone 
• 159590-16-6 3,3'-(perfluorocyclopent-1-ene-1,2-diyl)bis(5-bromo-2-methylthiophene) 
• 868134-76-3 1-(4-bromo-5-methyl-thiophen-2-yl)-1-phenyl-prop-2-yn-1-ol 
• 868134-77-4 3-(4-bromo-5-methylthiophen-2-yl)-3-phenyl-[3H]-naphto[2,1-b]pyran 

Relevant articles and documents

Cope Rearrangement in the Thiophene Series

The inability to observe Cope rearrangement at elevated temperature for diethyl α-allylphenylmalonate does not extend to the analogous systems resulting from replacement of the benzene ring by 2- and 3-thiophene nuclei.Thermal rearrangement of diethyl α-allyl-2-thienylmalonate (5) at 250-260 deg C for 12 h produces the expected Cope rearrangement product diethyl (3-allyl-2-thienyl)malonate (6) (49percent) accompanied by ethyl 6-carboethoxy-5,6-dihydro-4H-5-cyclopentathiopheneacetate (7) (28percent).The structural verification of 6 was obtained by degradation to 3-allyl-2-methylthiophene which was compared with an authentic sample obtained by synthesis.The structure of 7 was based on analogy.Similar results were observed with the 3-substituted analogues of 5, both diethyl (2-allyl-3-thienyl)malonate (14) and ethyl 4-carboethoxy-5,6-dihydro-4H-5-cyclopentathiopheneacetate (15) being formed.In this case the structure of 14 was verified by synthesis.Speculative mechanistic considerations are offered regarding the mode of transformation of 6 to 7 and 14 to 15.That the methine proton of the malonate substituent in 6 and 14 is involved in this transformation is seen by the inability of the appropriate methyl-substituted derivative of 6 to undergo thermal cyclization.

Remarkably Efficient Iridium Catalysts for Directed C(sp2)-H and C(sp3)-H Borylation of Diverse Classes of Substrates

Here we describe the discovery of a new class of C-H borylation catalysts and their use for regioselective C-H borylation of aromatic, heteroaromatic, and aliphatic systems. The new catalysts have Ir-C(thienyl) or Ir-C(furyl) anionic ligands instead of the diamine-type neutral chelating ligands used in the standard C-H borylation conditions. It is reported that the employment of these newly discovered catalysts show excellent reactivity and ortho-selectivity for diverse classes of aromatic substrates with high isolated yields. Moreover, the catalysts proved to be efficient for a wide number of aliphatic substrates for selective C(sp3)-H bond borylations. Heterocyclic molecules are selectively borylated using the inherently elevated reactivity of the C-H bonds. A number of late-stage C-H functionalization have been described using the same catalysts. Furthermore, we show that one of the catalysts could be used even in open air for the C(sp2)-H and C(sp3)-H borylations enabling the method more general. Preliminary mechanistic studies suggest that the active catalytic intermediate is the Ir(bis)boryl complex, and the attached ligand acts as bidentate ligand. Collectively, this study underlines the discovery of new class of C-H borylation catalysts that should find wide application in the context of C-H functionalization chemistry.

Practical preparation of ethyl 2-methylthiophene-3-carboxylate

A safe and efficient process for the preparation of ethyl 2-methylthiophene-3-carboxylate (5) was devised. This process provides several advantages over the precedents, involving operational simplicity, avoidance of the use of strong bases such as n-butyllithium and application of noncryogenic conditions, and enabled to prepare 5 in 52% overall yield from commercially available 2-methylthiophene on a multikilogram scale.