2-Amino-5-bromopyridine → 2-(Boc-amino)-5-bromopyridine

Temperature

0 °C

To a solution of 2-amino-5-bromopyridine (8.65 g, 50 mmol) in THF (100 mL) was added lithium hexamethyldisilazide (105 mL, 105 mmol) under nitrogen at 0° C. After the addition, the mixture was stirred for 30 mins at 0° C. At this point, (BOC)2O (12 g, 55 mmol) was added to the reaction mixture and the mixture was stirred for another 30 mins at 0° C. TLC (petroleum ether/ethyl acetate=5:1) indicated the reaction was complete. The reaction mixture was washed with 1 N HCl (20 mL), and the residue was extracted with ethyl acetate (50 mL×3). The combined organic layers were washed with brine, dried over Na2SO4, and evaporated in vacuo. The residue was purified by chromatography on silica to afford (I-29a) (8 g, 58.6%) as a white solid.

1. additionAfter the addition
2. stirringthe mixture was stirred for another 30 mins at 0° C
3. washThe reaction mixture was washed with 1 N HCl (20 mL)
4. extractionthe residue was extracted with ethyl acetate (50 mL×3)
5. washThe combined organic layers were washed with brine
6. dry with materialdried over Na2SO4
7. customevaporated in vacuo
8. customThe residue was purified by chromatography on silica
9. customto afford (I-29a) (8 g, 58.6%) as a white solid

ORD record

ord-4fd6d4f504eb4127bc40a62938ce6b2b

Source dataset

uspto-grants-2012_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08329920B2