3,4-Dimethoxythiophene

Colorless to yellow to orange liquid

3,4-Dimethoxythiophene (DMOT) is a monomer and a precursor which can be synthesized by ring closure reaction of 2,3-dimethoxy-1,3-butadiene and sulfur dichloride in hexane medium. It is an oligothiphene that is majorly used in the development of electroactive materials for organic electronics based applications.

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 22.6percent 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 wtpercent 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: 81.5percent) of 3, 4-dimethoxythiophene. The purity of its 3, 4-dimethoxythiophene was 98.01percent 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.Step 3: Synthesis of Chloromethyl-3, 4-ethylenedioxythiophene for conversion to EDOT-MEOH:; 1) 3, 4-dimethoxythiophene synthesis from 3, 4-dibromothiophene for the improved EDOT-MeOH synthesis:; [0084] Sodium methoxide was prepared by slow addition of small cubes of sodium metal (25 g, 1.05 mol) to ice bath cooled anhydrous methanol (600 mL) in a 1 L 3-necked flask equipped with a reflux condenser under a nitrogen blanket. Between additions of the sodium it was covered in kerosene to exclude moisture. After complete dissolution of the sodium, 50 g (0.207 mol) of 3, 4- dibromothiophene, 16.5 g (0.207 mol) copper (II) oxide, and 1.37 g (0.00827 mol) potassium iodide was added to the reaction mixture. The reaction was refluxed for three days. The reaction was then cooled to room temperature and filtered through a sintered glass fritted funnel. The resulting solid was rinsed with ether and the filtrate was poured into 500 mL water. The solution was then extracted with ether. The organic fractions were combined and dried with magnesium sulfate. Solvent removal gave a light yellow oil. Vacuum distillation gave 26.2 g of a clear, colorless oil whose structure and purity were confirmed by ^H and ^C NMR and GC-MS. Yield was 88percent of theoretical.A synthesis method of 3, 4-dimethoxythiophene, In a volume of 1000ml, In a pressure-resistant 3MPa stainless steel test reactor, Join Methyl 2, 5-dicarboxylate-3, 4-dimethoxythiophene 100g (purity 98.6percent), Soluble in dimethylformamide Aqueous DMF, The mass of dimethylformamide is 265g. Water 35g, Then add CuO 3g, Close the reactor and heat it with stirring. Keep the reaction temperature at 170±5°C Control reaction pressure at 6±0.5kg/cm2 (table) The reaction is 8.5 hours under the condition of heat preservation and pressure keeping. After the reaction is completed, Hot filter, Filter residue plus a small amount of DMF washing, The washing liquid and the filtrate are combined to vacuum distillation. The product was 3, 4-dimethoxythiophene, 52.37 g, Purity 98.9percent, The yield was 94.8percent. The rectified DMF solution can be recycled.A mixture of 21.78 g 1 (0.09 mol), 150 cm(1), under a nitrogen atmosphere, 28 ml of toluene, 1.36 g, 10.4 mmol of 2) Synthesis of 2-(chloromethyl)-2, 3-dihydrothieno[3, 4-b][l, 4]dioxine:; [0085] Under a nitrogen atmosphere in a 500 mL round bottom flask equipped with a reflux condenser, 20.0 g (0.139 mol) dimethoxythiophene, 17.8 g (0.161 mol) 3-chloro-l, 2-propanediol, and 5 g p-toluenesulfonic acid was dissolved in 350 mL toluene. The reaction was then heated to -90 C overnight. At this time TLC indicated consumption of starting material. After cooling the reaction mixture was concentrated to -100 mL and poured into saturated potassium carbonate solution. The mixture was extracted with DCM and the combined extracts were dried with magnesium sulfate. Solvent removal gave a dark oil that was purified by column chromatography using 3: 1 hexanes/DCM. Solvent removal gave the product as a white solid. Structure and purity were confirmed by 1Hy13C NMR and LC-MS.10623] The first step of the synthesis is the transetherification of Step 4:

The structural unit of N2S2-N4 porphyrin dimer was synthesized and used to study light-induced energy transfer.

3,4-Dimethoxythiophene is used as an electronic materials intermediate. It is used as a starting material in the synthesis of porphyrin dyad which is used to study photoinduced energy transfer.

Molecular Weight:144.19
XLogP3:1.5
Hydrogen Bond Acceptor Count:3
Rotatable Bond Count:2
Exact Mass:144.02450067
Monoisotopic Mass:144.02450067
Topological Polar Surface Area:46.7
Heavy Atom Count:9
Complexity:77.1
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes