Synthesis
The general procedure for the synthesis of 2,4-dihydroxybenzonitrile from 2,4-dihydroxybenzaldehyde oxime was as follows: n-C4F9SO2F (20.0 mmol, 2.0 eq.) was slowly added dropwise using a syringe to a solution of n-C4F9SO2F (20.0 mmol, 2.0 eq.) containing substrate 2,4-dihydroxybenzaldehyde oxime (10.0 mmol) and 1,8-diazabicyclo[5.4.0]undec-7-ene ( DBU, 50.0 mmol, 5.0 equiv) in a solution of dichloromethane (CH2Cl2, 20 mL). The reaction mixture was stirred at the same temperature for 10 min. Subsequently, the volatile components were removed by distillation under reduced pressure to obtain the crude product. The crude product was purified by silica gel column chromatography with the eluent being a solvent mixture of petroleum ether and ethyl acetate, resulting in the target product 2,4-dihydroxybenzonitrile in 95% yield.
References
[1] Synthetic Communications, 2013, vol. 43, # 13, p. 1778 - 1786
[2] Chinese Chemical Letters, 2016, vol. 27, # 1, p. 96 - 98
[3] Journal of the American Chemical Society, 1995, vol. 117, # 32, p. 8312 - 8321
[4] Soft Matter, 2011, vol. 7, # 18, p. 8266 - 8280
[5] Advanced Functional Materials, 2014, vol. 24, # 12, p. 1703 - 1717
