ChemicalBook CAS DataBase List 3,4-Dimethoxythiophene

3,4-Dimethoxythiophene synthesis

9synthesis methods

Product Name:3,4-Dimethoxythiophene
CAS Number:51792-34-8
Molecular formula:C6H8O2S
Molecular Weight:144.19

3141-26-2 Synthesis

3141-26-2
311 suppliers
$5.00/1g

124-41-4 Synthesis

124-41-4
716 suppliers
$12.00/25g

51792-34-8
330 suppliers
$6.00/1g

Yield:51792-34-8 81.5%

Reaction Conditions:

with copper(I) bromide in methanol at 70 - 97;Inert atmosphere;Temperature;

Steps:

1 Preparation of 3,4-dimethoxythiophene from 3,4-dibromothiophene
21 g of sodium methoxide and 72 g of methanol were added to a 100 ml four-necked flask (the concentration of sodium methoxide relative to the methanol solvent was 22.6% by weight based on the total amount of sodium methoxide before the reaction) and dissolved at 70 under an argon atmosphere.After addition of 0.83 g of cuprous bromide, 15 g of 3,4-dibromothiophene was added dropwise, and the reaction solution became colorless transparent to black. After completion of the dropwise addition, 50 g of methanol was distilled off (sodium methoxide to methanol solvent The concentration was 48.8 wt% based on the total amount of sodium methoxide before the reaction)The reaction was heated to reflux at 97 .When the reaction was traced by gas chromatography, 3,4-dibromothiophene and 3-bromo-4-methoxythiophene were found to be below the detection limit at the reflux starting time of 5 hours.After water was added to the reaction mixture and the mixture was filtered, the crude product was extracted from toluene, and the toluene layer was washed with water, and then the toluene layer was dried with magnesium sulfate.After the magnesium sulfate was removed by filtration, the toluene layer was concentrated by a rotary evaporator and then subjected to vacuum distillation to obtain 7.28 g (yield: 81.5%) of 3,4-dimethoxythiophene. The purity of its 3,4-dimethoxythiophene was 98.01% by gas chromatography.The purity (concentration) by gas chromatography in the present invention was indicated by the area ratio of the peak area obtained by the detection device by FID using Agilent 6890N network GC manufactured by Aglient Technologies.

References:

Nippon Karitto Corporation;Koga, Minekaju;Nishiyama, Masaki;Yisikita, Yoshihito;Kiryu, Toshiyuki;Yamaguchi, Yoji KR101558628, 2015, B1 Location in patent:Paragraph 0184-0190

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3141-26-2 Synthesis

3141-26-2
311 suppliers
$5.00/1g

51792-34-8
330 suppliers
$6.00/1g

References