Trimethylsilylacetylene → 5-Chloro-3-((trimethylsilyl)ethynyl)pyridin-2-amine

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A suspension of 2.54 g of 5-chloro-3-iodopyridin-2-ylamine, 2.12 ml of ethynyltrimethylsilane, 0.38 g of copper iodide and 0.47 g of lithium chloride in 7 ml of triethylamine and 75 ml of dimethylformamide is degassed under argon for approximately 15 minutes. 0.408 g of [1,1′-bis(diphenylphosphino)ferrocene] palladium(II) chloride is added to the above suspension. The mixture is heated at around 40° C. for approximately 19 hours and then concentrated to dryness under reduced pressure (13 kPa). The residue is taken up with 50 ml of water, and extracted with three times 100 ml of ethyl acetate. The combined organic phases are dried over magnesium sulfate, filtered, and concentrated to dryness under reduced pressure (13 kPa). The residue is purified by flash chromatography on a silica column [eluent: cyclohexane/ethyl acetate (70/30 by volume)]. 1.63 g of 5-chloro-3-trimethylsilanylethynylpyridin-2-ylamine are obtained in the form of a solid, the characteristics of which are as follows:

Herkunft & Nachweise