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

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

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.

Herkunft & Nachweise