5-BroMo-1,2,3-triazine synthesis

Yield:114078-88-5 25 g

Reaction Conditions:

Stage #1:4-bromo-1H-pyrazole with sodium hydroxide;hydroxylamine-O-sulfonic acid in water for 0.5 h;
Stage #2: with sodium periodate in water at 0;

Steps:

1.1 1. Synthesis of Intermediate 1-2:
To a solution of 4-bromo-1H-pyrazole (50 g, 340 mmol, 1.0 equiv) in sodium hydroxide (3.7 N, 555 mL) was added (aminooxy)sulfonic acid (116 g, 1.0 mol, 3.0 equiv). The mixture was stirred for 30 min and extracted with DCM (500 mL). The organic layer was washed with brine (200 mL) twice, dried over anhydrous sodium sulfate, concentrated under reduced pressure, and poured into DCM (400 mL) and water (200 mL). To the resulting solution was added NaIO₄ (147 g, 685 mmol, 2.0 equiv) at 0 ^oC. The mixture was stirred overnight, diluted with DCM (500 mL), washed with brine (200 mL) twice, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to afford 25 g of 5- bromo-1,2,3-triazine as brown oil.

References:

CYTOKINETICS, INC.;CHUANG, Chihyuan;MORGAN, Bradley P.;VANDERWAL, Mark;WANG, Wenyue;ASHCRAFT, Luke W. WO2019/144041, 2019, A1 Location in patent:Paragraph 0203

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