Hydrochloric Acid → 4-[(E)-3-oxo-3-(2-phenylamino-pyridin-3-yl)-propenyl]-benzoic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

A solution of 1-(2-phenylamino-pyridin-3-yl)-ethanone (2.13 g, 10.0 mmol) in methanol (42 mL, 0.24M) was treated with sodium methoxide (25% wt. solution methanol, 4.6 mL, 20.1 mmol) and methyl 4-formylbenzoate (2.04 g, 12.4 mmol). The reaction was stirred at 25° C. over 3 d. At this time, the reaction was diluted with water (100 mL), acidified with a 1N aqueous hydrochloric acid solution, and extracted with a 10% methanol/methylene chloride solution. The combined organics were dried over magnesium sulfate, filtered, rinsed with methylene chloride, and concentrated onto silica gel in vacuo. Flash chromatography (AnaLogix Intelliflash 280, 80 g silica gel column, 20% ethyl acetate/hexanes) afforded 4-[(E)-3-oxo-3-(2-phenylamino-pyridin-3-yl)-propenyl]-benzoic acid methyl ester (3.43 g, 95%) as an orange solid.

Provenance & Evidence