ChemicalBook CAS DataBase List 2-Methyl-3-thiophenecarboxylic acid methyl ester

2-Methyl-3-thiophenecarboxylic acid methyl ester synthesis

4synthesis methods

Product Name:2-Methyl-3-thiophenecarboxylic acid methyl ester
CAS Number:53562-51-9
Molecular formula:C7H8O2S
Molecular Weight:156.2

67-56-1

1918-78-1

2-Methyl-3-thiophenecarboxylic acid methyl ester

53562-51-9

General procedure for the synthesis of methyl 2-methyl-3-thiophenecarboxylate from methanol and 2-methyl-3-thiophenecarboxylic acid: thionyl chloride (200 mL, 2.76 mol) was added slowly and dropwise to a solution of 2-methyl-3-thiophenecarboxylic acid (100 g, 703 mmol) in methanol (500 mL). After stirring the reaction mixture under reflux conditions for 3 h, it was concentrated under reduced pressure. The concentrated residue was diluted with dichloromethane, washed sequentially with water, saturated aqueous sodium bicarbonate solution and brine, and then dried over anhydrous sodium sulfate. After filtration, the solvent was removed by concentration under reduced pressure to give 105 g (96% yield) of methyl 2-methyl-3-thiophenecarboxylate as a brown oil. Its NMR hydrogen spectrum (400 MHz, CDCl3) data were as follows: δ 7.38 (d, J = 5.4 Hz, 1H), 6.98 (d, J = 5.4 Hz, 1H), 3.85 (s, 3H), 2.74 (s, 3H); Mass Spectrometry (ESI) m/z: 157 (M + H)+.

67-56-1 Synthesis

67-56-1
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1918-78-1 Synthesis

1918-78-1
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$9.00/250mg

53562-51-9
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$52.00/1g

Yield: 96%

Reaction Conditions:

with thionyl chloride for 3 h;Reflux;

Steps:

4.1.3 Methyl 2-methylthiophene-3-carboxylate (10)
Thionyl chloride (200mL, 2.76mol) was slowly added dropwise to a solution of 9 (100g, 703mmol) in MeOH (500mL). After stirring at reflux for 3h, the mixture was concentrated under reduced pressure. The residue was diluted with CH₂Cl₂, washed with water, saturated aqueous NaHCO₃ and brine, and dried over Na₂SO₄. After filtration, the solvent was concentrated under reduced pressure to give 105g (96%) of 10 as a brown oil: ¹H NMR (400MHz, CDCl₃) δ 7.38 (d, J=5.4Hz, 1H), 6.98 (d, J=5.4Hz, 1H), 3.85 (s, 3H), 2.74 (s, 3H); MS (ESI) m/z: 157 (M+H)⁺.

References:

Fujieda, Hiroki;Kogami, Masakazu;Sakairi, Masao;Kato, Noriyasu;Makino, Mitsuhiro;Takahashi, Naoki;Miyazawa, Toshiyuki;Harada, Satoko;Yamashita, Tokuyuki [European Journal of Medicinal Chemistry,2018,vol. 156,p. 269 - 294]

40018-26-6 Synthesis