Ethyl propiolate → HCID 15013402, compound

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of ethyl prop-2-ynoate (5.98 g, 60.96 mmol, 1.00 equiv) in anhydrous tetrahydrofuran (60 mL) maintained under nitrogen at −65° C. was added dropwise a 2.5M solution of n-BuLi (28 mL, 1.50 equiv) in hexanes. The reaction mixture was stirred at −65-40° C. for 1 h then a 0.7M solution of ZnCl2 (170 mL, 2.00 equiv) in THF was added. The resulting solution was stirred at room temperature for 30 min. 4-iodobenzonitrile (6.87 g, 30.00 mmol, 0.50 equiv) was then added in portions followed by the addition of Pd(PPh3)Cl2 (1.05 g, 1.00 equiv). The resulting mixture was stirred at 50° C. for 5 h and then quenched by the addition of 150 mL of saturated NH4Cl solution. The mixture was extracted with 3×100 mL of ether. The combined organic layers was dried over anhydrous sodium sulfate and concentrated under vacuum. The residue was purified on a silica gel column eluted with 0-10% of methanol in dichloromethane to give 3.25 g (27%) of ethyl 3-(4-cyanophenyl)propiolate as a white solid.

Provenance & Evidence