Trimethylsilylacetylene → 2-Chloro-3-fluoro-4-methyl-5-((trimethylsilyl)ethynyl)pyridine

Participants

Reaction Conditions

Reaction Steps

A mixture of 2-chloro-3-fluoro-5-iodo-4-methyl-pyridine (2960 mg, 10.9 mmol), ethynyltrimethylsilane (1.89 mL, 13.1 mmol), N,N-diisopropylethylamine (3.80 mL, 21.8 mmol), dichlorobis(triphenylphosphine)palladium(II) (390 mg, 0.545 mmol), and cuprous iodide (104 mg, 0.55 mmol) in dioxane (40 mL) was heated at 60° C. for 2 hours. The reaction mixture was filtered through a short plug of silica, rinsed with 50 mL of ethyl acetate/heptane (1:1), and the filtrate was evaporated in vacuo to provide an orange oil that was purified by flash chromatography (12 g, Silica, 0-20% ethyl acetate in heptane). Desired fractions were combined and evaporated in vacuo to afford the title compound as a pale yellow oil, (2.35 mg, 89%). 1H NMR (400 MHz, CDCl3) δ 8.21 (s, 1H), 2.40 (d, J=1.9 Hz, 3H), 0.28 (s, 11H).

Provenance & Evidence