5-Bromo-2-chloropyrimidine synthesis

6synthesis methods

Product Name:5-Bromo-2-chloropyrimidine
CAS Number:32779-36-5
Molecular formula:C4H2BrClN2
Molecular Weight:193.43

Under nitrogen protection, 35 g (0.2 mol) of 2-hydroxy-5-bromopyrimidine, 61.3 g (0.4 mol) of phosphorus oxychloride, and 200 mL of toluene were added into the reaction flask. At 35 ℃, triethylamine 40.5g was added and then heated up at 80-85 ℃. Stir the reaction for 6 hours, sampling HPLC to detect the raw material (less than 2%), and lower the temperature. After concentrating the mixture under reduced pressure to remove most of the toluene and Phosphorus oxychloride, put the reaction solution into 10°C water, and adjust pH=8-9 with 20% sodium carbonate aqueous solution. Finally, 5-Bromo-2-chloropyrimidine was obtained after purification.

38353-06-9
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32779-36-5
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$5.00/5g

Yield:32779-36-5 91%

Reaction Conditions:

with hydrogenchloride;trimethylhexadecylammonium chloride in lithium hydroxide monohydrate;N,N-dimethyl-formamide at 40; for 12 h;Temperature;

Steps:

1.2; 2.2; 3.2; 4.2; 5.2; 6.2; 7.2 Preparation of 5-bromo-2-chloropyrimidine:

Take a dry 500mL three-necked bottle,Add 14g of 5-bromo-2-hydroxypyrimidine and 280mL of DMF, start stirring, add 5.12g of cetyltrimethylammonium chloride and 20mL of 6mol.L-1 hydrochloric acid, then place the three-necked flask at 40 oil bath, stirring for 12h,Drop to 0°C, adjust the pH to 6 with saturated sodium bicarbonate solution, extract three times with ethyl acetate, combine the organic phases,The organic phase was washed once with saturated brine, dried over anhydrous sodium sulfate, and concentrated to dryness to obtain 14.1 g of 5-bromo-2-chloropyrimidine with a yield of 91% and a purity of 99.76%.

References:

CN114644594,2022,A Location in patent:Paragraph 0020; 0023; 0025-0026; 0029-0030; 0033-0034; ...

4595-59-9 Synthesis