Synthesis
The general procedure for the synthesis of 1-(4-morpholinyl)-2-propyne from morpholine and 3-bromopropargyl was as follows: morpholine (100 mL, 1.148 mol) was dissolved in methanol (1 L) and cooled in an ice bath under nitrogen protection. Subsequently, potassium carbonate (120 g, 0.63 mol) and propargyl bromide (124 mL, 1.148 mol) were sequentially added under ice bath stirring conditions. The reaction mixture was continued to be stirred without cooling for 4 hours. After completion of the reaction, the resulting white suspension was filtered through filter paper and the solid residue was washed with methanol (100 mL). The filtrates were combined and methanol was removed by careful evaporation. The white precipitate obtained was suspended in dichloromethane (400 mL), filtered again through filter paper and the solvent was carefully evaporated. Finally, the product was distilled under reduced pressure at 60 °C and 16 mbar to give 100 g of colorless oily product in 70% yield.
References
[1] Journal of Organometallic Chemistry, 1983, vol. 244, # 4, p. 311 - 318
[2] Journal of Combinatorial Chemistry, 2010, vol. 12, # 4, p. 491 - 496
[3] Journal of the American Chemical Society, 2014, vol. 136, # 12, p. 4740 - 4745
[4] Green Chemistry, 2009, vol. 11, # 8, p. 1115 - 1120
[5] Journal of the Chemical Society, Perkin Transactions 2: Physical Organic Chemistry (1972-1999), 1982, p. 1459 - 1466
