Triethylamine → HCID 9855675, compound

Participants

Reaction Steps

2-Bromo-1,3-thiazole (0.15 mL, 1.6 mmol), CuI (98 mg, o.51 mmol), PdCl2(PPh3)2 (120 mg, 0.17 mmol) and triethylamine (2.8 mL, 20 mmol) were combined in DMF (6.8 mL) and cooled in an ice bath. 3-Ethynylpyridine (520 mg, 5.04 mmol) was then added to the mixture as a solution in DMF (3.0 ML). The ice bath was removed and the reaction was allowed to stir at ambient temperature for 16 h. The reaction mixture was filtered through a pad of Celite.™, and the pad was washed thoroughly with ethyl acetate. The filtrate was washed with brine (3.times.20 mL). A partial emulsion was observed. The mixture was concentrated in vacuo and the residue was taken up in CH2Cl2, washed with brine, dried over Na2SO4, filtered and concentrated in vacuo. The crude product was purified by column chromatography on silica gel eluting with 80:20 followed by 30:20 hexane:ethyl acetate to afford 3-(1,3-thiazol-2-ylethynyl)pyridine (160 mg) as a mixture with another product exhibiting a mass of 204 in the GC/MS, assigned as pyridylalkyne dimer. A portion of the mixture (100 mg) was further purified by preparative reverse phase HPLC eluting with a gradient of 80:20 to 0:100 water: acetonitrile over twenty minutes. The fractions containing the desired product were collected (detection by uv at 210 nm) to afford 3-(1,3-thiazol-2-ylethynyl)pyridine as a white waxy solid (15 mg). 1H NMR (CDCl3, 300 MHz) Δ9.3-8.5 (br s, 2H), 7.92-7.90 (m, 2H), 7.50-7.30 (m, 2H). MS (ESI) 187.0 (M++H).

Provenance & Evidence