Ethyl Acetate → 5-Bromo-2-((tert-butyldimethylsilyl)ethynyl)pyridine

Participants

Reaction Conditions

Reaction Steps

Under an argon atmosphere, 0.80 g (4.20 mmol) of CuI and 2.90 g (4.13 mmol) of bis(triphenylphosphane)palladium (II) chloride are added to a solution of 49.90 g (201.0 mmol) of 2,5-dibromopyridine and 43.0 mL (225.6 mmol) of tert-butylethynyldimethylsilane in 500 mL of dry THF and 120 mL of triethylamine at −7° C. and the mixture is stirred for 30 minutes at 0° C. The reaction mixture is stirred for a further 3.5 hours at RT, then filtered, and the filtrate is evaporated down in vacuo. The residue is dissolved in 1 L of EtOAc, and the organic phase is washed with water and saturated NaCl solution, dried over sodium sulfate (Na2SO4), and evaporated down in vacuo. The crude product is further reacted without purification. Yield: 59.5 g (quant. yield); C13H18BrNSi (M=296.278); calc.: molpeak (M+H)+: 296/298 (Br); found: molpeak (M+H)+: 296/298 (Br); Rf value: 0.75 (silica gel, Cyc/EtOAc 8:1).

Provenance & Evidence