Chlorotrimethylsilane → 2-(2-Amino-5-bromobenzoyl)pyridine

Temperatur

-40 °C

To a −40° C. solution of 2.5 M n-BuLi (18 mL) in THF (300 mL) is added 2-bromopyridine (5.0 g, 32 mmol) over 15 min. The reaction is stirred for 1 h at −40° C., and then treated with 2-Amino-5-bromo-benzoic acid (6.9 g, 32 mmol) in THF (300 mL). The reaction is warmed to 0° C. and stirred for 2 h then quenched with TMSCl (3.4 g, 32 mmol). The reaction is stirred at room temperature for 30 min then cooled to 0° C. and quenched with 3M HCl (20 mL). The aqueous layer is separated and the organic layer is extracted with 3M HCl. The organic layer is basified with solid NaOH, the resulting mixture is extracted with EtOAc, and the organic layer is dried over Na2SO4, filtered and concentrated. The residue is purified by column chromatography on silica gel to give the desired product as a yellow solid.

1. temperatureThe reaction is warmed to 0° C.
2. stirringstirred for 2 h
3. stirringThe reaction is stirred at room temperature for 30 min
4. temperaturethen cooled to 0° C.
5. customquenched with 3M HCl (20 mL)
6. customThe aqueous layer is separated
7. extractionthe organic layer is extracted with 3M HCl
8. extractionthe resulting mixture is extracted with EtOAc
9. dry with materialthe organic layer is dried over Na2SO4
10. filtrationfiltered
11. concentrationconcentrated
12. customThe residue is purified by column chromatography on silica gel

ORD-Eintrag

ord-3ec8b49e86bc4701af31b24a5acb130e

Quelldatensatz

uspto-grants-2015_12

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09199988B2