Synthesis
General procedure for the synthesis of 4-ethynylbenzaldehyde from 4-trimethylsilylethynylbenzaldehyde: Compound 4 (727 mg, 3.6 mmol) was dissolved in 15 mL of anhydrous THF, followed by the addition of 2 mL of aqueous KOH (298 mg, 4 mmol). The reaction mixture was stirred at room temperature for 2 hours. Upon completion of the reaction, the THF solvent was removed by rotary evaporator. The reaction mixture was extracted with ethyl acetate (EA) and washed three times with saturated NaCl solution. The combined organic phases were dried with anhydrous Na2SO4, filtered and concentrated. Finally, purification by column chromatography (eluent was petroleum ether and dichloromethane, 1:1, v/v) gave 450 mg of compound 5 as a light yellow solid in 97% yield.
References
[1] Journal of the American Chemical Society, 2009, vol. 131, # 2, p. 634 - 643
[2] Chemical Communications, 2011, vol. 47, # 4, p. 1282 - 1284
[3] Journal of Materials Chemistry A, 2013, vol. 1, # 34, p. 10008 - 10015
[4] ChemPhysChem, 2016, p. 2066 - 2078
[5] Journal of the American Chemical Society, 2016, vol. 138, # 51, p. 16703 - 16710
