Triethylamine → HCID 101451949, compound

Participants

Reaction Steps

In a flask placed under an argon flow, 1.82 g (5.77 mmol) of ethyl 3-iodoimidazo[1,2-a]pyridine-2-carboxylate were dissolved in 6 ml of dimethylformamide with magnetic stirring. To this solution were added: 0.11 g (0.577 mmol) of copper iodide, 0.776 ml (6.93 mmol) of phenylacetylene and 6 ml (43 mmol) of triethylamine. The reaction medium was degassed with argon for 10 min before adding 0.529 g (0.577 mmol) of Pd2(dba)3. The mixture was stirred at r.t. for 16 h before being filtered on celite. The celite was washed with 50 ml of ethyl acetate, and then the filtrate was washed with 2×50 ml of water. After separation, the aqueous phase was extracted with 2×50 ml of ethyl acetate; the combined organic phases were washed with 70 ml of a saturated NaCl aqueous solution, dried on Na2SO4 which was then removed by filtration. The obtained filtrate was concentrated in vacuo. The crude residue was purified by flash chromatography on a silica gel cartridge (eluent: heptane/ethyl acetate, 6/4, v/v). 1.28 g (yield=57%) of ethyl 3-(phenylethynyl)imidazo[1,2-a]pyridine-2-carboxylate were obtained as a pale yellow solid. LC-MS: m/z=291 (MH+); UV purity at 254 nm=93%. 1H NMR (300 MHz, DMSO) δ 8.70 (d, J=6.8 Hz, 1H), 7.74 (dd, J=22.1, 6.2 Hz, 3H), 7.53 (dd, J=17.6, 6.9 Hz, 4H), 7.23 (t, J=6.3 Hz, 1H), 4.36 (d, J=4.7 Hz, 2H), 1.36 (d, J=7.1 Hz, 3H).

Provenance & Evidence