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ChemicalBook CAS DataBase List 5-bromo-4-chloropyridine-2,3-diamine
1131604-99-3

5-bromo-4-chloropyridine-2,3-diamine synthesis

3synthesis methods
942947-95-7 Synthesis
2-Amino-5-bromo-4-chloro-3-nitropyridine

942947-95-7
96 suppliers
$25.00/250mg

-

Yield:-

Reaction Conditions:

with acetic acid;zinc at 20; for 3.33333 h;

Steps:

30
General procedure: To a solution of 4,5-dichloro-3-nitropyridin-2-amine (300 mg, 1.44 mmol) in 5 mL AcOH was added portionwise zinc dust (472 mg, 7.2 mmol) over 20 min.
After addition, the mixture was stirred for another 3 h then added dropwise to 100 mL saturated Na2CO3 and extracted with ethyl acetate.
The combined extracts were washed with brine, dried, evaporated and purified by column chromatography to give 4,5-dichloropyridine-2,3-diamine (148 mg, 57.5%). 5.2.2.31
7-Bromo-8-chloro-1,4-dihydropyrido[2,3-b]pyrazine-2,3-dione (31)
To a solution of 2-amino-4-chloropyridine (1.28 g, 10.0 mmol) in anhydrous CH3CN (40 mL) was added portionwise N-bromosuccinimide (1.96 g, 11.0 mmol).
The reaction mixture was stirred at room temperature for 24 h then poured into 100 mL ice-water and extracted with ethyl acetate.
The combined extracts were washed with 1 M NaOH and brine, dried and evaporated.
The residue was purified by column chromatography on silica gel to give 5-bromo-4-dichloropyridin-2-amine (1.53 g, 60.8%).
Next steps followed the procedure of 30 and gave the title compound as white solid (63 mg, 12.5% over 3 steps).

References:

Xie, Dongsheng;Lu, Jun;Xie, Jin;Cui, Junjun;Li, Teng-Fei;Wang, Yan-Chao;Chen, Yuan;Gong, Nian;Li, Xin-Yan;Fu, Lei;Wang, Yong-Xiang [European Journal of Medicinal Chemistry,2016,vol. 117,p. 19 - 32]

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