PA-CI

Synthesis of Propargyl Carbonylimidazole (PA-CI)

A dry round-bottomed flask was charged with 29.19 g (180 mmol) of CDI and 200 mL of dichloromethane to yield a turbid suspension. Propargyl alcohol (5.82 mL, 100 mmol) was added under vigorous stirring to yield a clear solution upon dissolution of the propargyl alcohol. After 1 h reaction at room temperature the mixture was extracted three times with 35 mL of water. The organic layer was dried over magnesium sulfate. After filtering off the magnesium sulfate, the liquid was evaporated by rotary evaporation and propargyl carbonylimidazole (PA-CI, 11.86 g, 79% yield) was obtained as a dry powder. 1H NMR spectra were
recorded with a Bruker AVANCE 500 MHz spectrometer. 1H NMR (CDCl3): d 1⁄4 2.6 (t, 1H, HC C), 5.0 (d, 2H, CH2 –O), 7.0 (s, 1H, C – CH –N), 7.4 (s, 1H, N –CH ––C), 8.1 (s, 1H, N –CH ––N).