Sodium hydride → 3-[5-(5-Chloro-thiophen-2-yl)-isoxazol-3-ylmethyl]-3H-imidazo[4,5-b]pyridine-2-carboxylic acid methyl ester

Participants

Reaction Steps

100 mg (0.56 mmol) 3H-Imidazo[4,5-b]pyridine-2-carboxylic acid methyl ester were dissolved in 3 mL DMF. 22.6 mg (0.56 mmol) sodium hydride (60% in mineral oil) were added and the mixture was stirred 30 minutes at room temperature. 157.2 mg (0.56 mmol) 3-Bromomethyl-5-(5-Chloro-thiophen-2-yl)-isoxazole were added and the resulting mixture was stirred for 1 h at 80° C. The reaction mixture was cooled to room temperature and after the addition of a few drops of water concentrated under reduced pressure. HPLC-MS-analysis showed the presence of another isomer (ratio of isomers≈7:1). Final purification by preparative RP-HPLC (CH3CN/H2O gradient+0.05% formic acid) gave pure 3-[5-(5-Chloro-thiophen-2-yl)-isoxazol-3-ylmethyl]-3H-imidazo[4,5-b]pyridine-2-carboxylic acid methyl ester as a brown amorphous solid.

Provenance & Evidence