Nitrogen → HCID 54687217, compound

Participants

Reaction Steps

A solution of propiophenone (1.50 mL, 11.3 mmol) in CH2Cl2 (40.0 mL) was cooled to 0° C. (N2 atmosphere) and treated with triethylamine (3.14 mL, 22.6 mmol) followed by trimethylsilyltriflate (2.60 mL, 13.5 mmol). The solution was then warmed to ambient temperature, allowed to stir for 15 min., and subsequently quenched into a mixture of diethyl ether (50 mL) and saturated aqueous NaHCO3 (20 mL). The layers were separated and the organic layer washed with a 1:1 mixture of brine:saturated NaHCO3 (20 mL). The ethereal solution was then dried with Na2SO4 and the solvent removed in vacuo. The resulting silyl enol ether was then transferred to a flask containing diethyl-2-(thiophenyl)propane-1,3-dioate (1.00 g, 3.76 mmol), the mixture heated to 140° C. for 16 h. then allowed to cool to room temperature where it was diluted with diethylether and extraced with saturated Na2CO3 (3×20 mL). The aqueous layers were combined, washed with diethylether (3×75 mL), then carefully acidified with conc. HCl. The mixture was then extracted with CH2 Cl2 (3×200 mL), the organic layers combined, dried with Na2SO4, and the solvent removed in vacuo to provide the title compound (0.350 g, m.p. 166°-167° C.). 1H NMR (400 MHz, DMSO-d6) δ 6.309-6.285 (m, 2 H), 6.227-6.211 (m, 3 H), 5.983 (t, 2 H, J=8 Hz), 5.862 (d, 3 H, J=8 Hz), 0.705 (s, 3 H).

Provenance & Evidence