2,4-Diaminopyrimidine → 5-Bromopyrimidine-2,4-diamine

Temperature

0 °C

To a mixture of 2,4-diaminopyrimidine (5.5 g, 0.05 mol, 1.0 eq.) and THF (200 ml) was added pyridinium tribromide (17.5 g, 0.055 mol, 1.1 eq) at 0° C. in three portions. The resulting mixture was stirred at about 0° C. for two hours, filtered and washed with THF (20 ml). The yellow solid was mixed with water (100 ml) and the resulting mixture was neutralized with 10% NaOH solution to a pH of about 7. Stirring was continued at room temperature for 30 minutes, after which the mixture was filtered, washed with water (2×20 ml) and dried under vacuum at 50° C. to give 8.2 g (87%) of 2,4-diamino-5-bromo-pyrimidine as a white solid. 1H NMR, HPLC and LCMS analyses of this product are identical to the product described in Step 1 of Example 1.

1. filtrationfiltered
2. washwashed with THF (20 ml)
3. additionThe yellow solid was mixed with water (100 ml)
4. stirringStirring
5. waitwas continued at room temperature for 30 minutes
6. filtrationafter which the mixture was filtered
7. washwashed with water (2×20 ml)
8. customdried under vacuum at 50° C.

ORD record

ord-2bd0dc1d70214e57aad3506b9ea10c31

Source dataset

uspto-grants-2010_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07781581B2