Continuously updated synthesis method about 20348-09-8

The synthetic route of 2H-Pyrido[3,2-b][1,4]oxazin-3(4H)-one has been constantly updated, and we look forward to future research findings.

Related Products of 20348-09-8, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 20348-09-8, name is 2H-Pyrido[3,2-b][1,4]oxazin-3(4H)-one belongs to amides-buliding-blocks compound, it is a common compound, a new synthetic route is introduced below.

To 2H-pyrido[3,2-b][1 ,4]oxazin-3(4H)-one (45.0 g, 300 mmol) in DMF (360 mL) at 20 C was added NBS (74.7 g, 420 mmol) in one portion, and the resulting brownish suspension was heated at 50 C for 20 hours. The mixture was cooled to 25 C, and the content was poured into stirred water (1 L) in a 3 L flask fitted with an overhead mechanical stirrer. The resulting aqueous suspension was stirred at room temperature for 30 minutes followed by filtration. The yellowish cake was washed with 10% Na2S203 solution (100 mL) followed by water (2 x 100 mL). The cake was aspirated at room temperature under house vacuum overnight. The solids were washed with Et20 (100 mL), aspirated under house vacuum at room temperature for 18 hours, and then dried under high vacuum at 50 C for 72 hours to afford the title compound (65.30 g) as a light tan-colored powdery solid. LC-MS (ES) m/z = 229, 231 [M+H]+. 1H NMR (400 MHz, DMSO-d6): delta 4.68 (s, 2H), 7.66 (d, J = 2.0 Hz, 1 H), 8.02 (d, J = 2.0 Hz, 1 H), 1 1 .44 (br. s., 1 H).

The synthetic route of 2H-Pyrido[3,2-b][1,4]oxazin-3(4H)-one has been constantly updated, and we look forward to future research findings.

Reference:
Patent; GLAXOSMITHKLINE INTELLECTUAL PROPERTY DEVELOPMENT LIMITED; MEDINA, Jesus Raul; TIAN, Xinrong; NG DI MARCO, Christina; GRAYBILL, Todd L.; HEERDING, Dirk A.; LI, William Hoi Hong; MANGATT, Biju; MARTYR, Cuthbert D.; RIVERO, Raphael Anthony; (570 pag.)WO2019/49061; (2019); A1;,
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