2-Chloro-5-methylpyridin-3-amine → (2-Chloro-5-methyl-pyridin-3-yl)-[2-(4-fluoro-phenyl)-1-pyridin-4-yl-ethylidene]-amine

Participants

Reaction Steps

A mixture of p-toluenesulfonic acid (500 mg), 2-(4-fluorophenyl)-1-(pyridine-4-yl)ethanone (10 g, 46 mmoles) and 5-methyl-3-amino-2-chloropyridine (8.6 g, 60 mmoles) in 350 mL of toluene was refluxed overnight with a Dean-Stark removal of water/toluene azeotrope. The reaction mixture was further concentrated, the brown residue suspended in an ethyl acetate/hexane mixture (9/1) and filtered. The solid was solubilised in ethyl acetate and purified by chromatography on silica gel (ethylacetate/hexane 1/1) to give 10 g of (2-Chloro-5-methyl-pyridin-3-yl)-[2-(4-fluoro-phenyl)-1-pyridin-4-yl-ethylidene]-amine as a brown solid.

Provenance & Evidence