3,6-DIBROMOTHIENO[3,2-B]THIOPHENE

The reactor was charged with C-1 (9 · 12g, 20 mmol), acetic acid 500 ml, toluene 200 ml, Zn powder (2.62 g, (5.36g, 90percent) was obtained by filtration, and the solution was concentrated and filtered to give the compound C-28-1 (5.36g, 90percent). After the reaction was carried out, The * Synthesis of Intermediate C-28-2In an inert atmosphere, the zinc powder (3.5g; 53.5 mmoles) is added in portions to the suspension of 2, 3, 5, 6-tetrabromothieno[3, 2-b]thiophene (14.6g; 32.2 mmoles) in 1 I of acetic acid. It is brought to 125°C. After 2 hours another portion of zinc is added (2.2g; 33.6 mmoles) and after 30 minutes another portion (0.8g; 12.2 mmoles). It is brought to 70°C and the zinc is removed by filtration. At 20°C, water is added to the filtrate and extracted with ethyl acetate. After washing the organic phase, first with a saturated aqueous solution of sodium bicarbonate and then to neutrality with water, it is dried over sodium sulfate. 7.6 g of 3, 6-dibromothieno[3, 2-b]thiophene of formula (V) are obtained with a 80percent yield:Accurately weigh the glacial acetic acid (300. OKg) into a dry 500 L autoclave through a high-level tank.A solid 5 (64.0 OKg, 140.4 mol, L Oeq.) Was added to the kettle, Zinc dust (27. 0 Kg, 415.4 mol, 3. Oeq) was added.Heating to 110 ° C for 1 hour.The reaction was followed by HPLC, When the raw material disappears, The reaction was stopped.After the reaction was complete, the temperature was lowered to 40-50 ° C, The solvent acetic acid was distilled off under reduced pressure, To the basic no liquid, Cooled to room temperature, Ethyl acetate (300. OKg) was added, Stir for 30 minutes.Filtration, washing the solids with ethyl acetate (20. 0 KgX2)The filtrates were combined, Into the reactor, Water (300. OKg) was added to the reaction kettle, Stirred for 20 minutes, Allow to stand for 20 minutes(If it is difficult to liquid, you can filter liquid after the separation).The aqueous phase was separated, The organic phase was left in the reactor, The organic phase (300. OKgX) was washed with 6.6percent sodium hydroxide in water, So that the aqueous phase pH> 7, and then to the reactor into the water (200. OKg) washed once, The organic phase was dried over sodium sulfate (30. OKg) for 2 hours.The organic phase was concentrated, Dry out to dryness, Solvent free product 10 (31.4 kg, 76.6percent).To a cooled (dry ice-acetone bath) solution of n-butyllithium (1.6 M in hexane, 4.7 mL, 7.5 mmol) in tetrahydrofuran (10 mL) was added dropwise a solution of In a 200 mL single-necked flask, 3, 6-dibromothiophene [3, 2-b] thiophene (5.0 g, 16.9 mmol), n-C8H17SH (1-octanethiol) (5.4 g, 36.9 mmol), DIEA ( 4.8g, 36.9mmol), DPPF (370mg, 0.7mmol), Pd2 (dba) 3 (310mg, 0.3mmol), added 80mL toluene, evacuated three times, and stirred under reflux at 110 C for 24h under nitrogen protection. Then, the reaction was cooled to room temperature, the mixture was poured into water, extracted with dichloromethane (3 × 50 mL), washed with water three times, dried over anhydrous magnesium sulfate, filtered, and the organic solvent was removed under reduced pressure. The column was separated using petroleum ether: dichloromethane (8: 1) as the eluent. the product was a yellow solid (5.32 g, 74% yield).

Molecular Weight:298.0
XLogP3:4.1
Hydrogen Bond Acceptor Count:2
Exact Mass:297.79442
Monoisotopic Mass:295.79647
Topological Polar Surface Area:56.5
Heavy Atom Count:10
Complexity:126
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes