Ethyl formate → HCID 70093552, compound

Participants

Reaction Steps

To a suspension of NaH (76 mg of a 60% dispension in oil, 1.9 mmol) in THF (5 ml,) was added ethyl formate (0.38 mL, 4.7 mmol) at 0° C. After stirring for 10 min a solution of 6,6-dimethyl-3-methylthio-1-(pyrrolidin-1-ylcarbonyl)-4,5,6,7-tetrahydrobenzo[c]thiophen-4-one (305 mg, 0.94 mmol) in THF (7 mL) was added. The cooling bath was removed and the mixture stirred at room temperature for 18 h. After this time MeOH (0.5 mL) followed by water (0.5 mL) were added and the mixture stirred for 10 min. The solvents were removed in vacuo and the residue dissolved in water. The mixture was acidified to pH1 using 1 M HCl and the resultant solid collected by filtration. The solid was partitioned between EtOAc (20 mL) and water (20 mL). The organic layer was separated, dried (Na2SO4) and evaporated. The residue was chromatographed on silica gel, eluting with EtOAc: DCM (10:90), to give the title compound (173 mg, 52%) as a pale yellow oil. 1H NMR (250 MHz, CDCl3) δ1.18 (6H, s),1.93-1.99 (4H, m), 2.63 (3H, s), 2.82 (2H, s), 3.56-3.70 (4H, m), 7.56 (1H, d, J=10.4 Hz), 14.63 (1H, d J=10.4 Hz).

Provenance & Evidence