GENERAL METHODS: A mixture of 4-hydroxybenzaldehyde (1 mmol), 2-chloroethanol (1 mmol) and potassium carbonate (3 mmol) in dimethylsulfoxide (DMSO) was heated and refluxed for 6 hours. The reaction process was monitored by thin layer chromatography (TLC). Upon completion of the reaction, the reaction mixture was diluted with water and extracted with dichloromethane. The organic phases were combined and concentrated under reduced pressure to remove the solvent, and the resulting residue was purified by column chromatography to afford the target product 4-(2-hydroxyethoxy)benzaldehyde (3m).
4.3.1. 4-(2-Hydroxyethoxy)benzaldehyde (3m) was a yellow oil in 80% yield; 1H NMR (400 MHz, CDCl3): δ 3.03 (1H, s, OH), 3.98 (2H, t, J = 4.4 Hz, -CH2-), 4.14 (2H, t, J = 4.4 Hz, -OCH2-), 6.98 (2H , d, J = 8.4 Hz, Ar-H), 7.80 (2H, d, J = 8.4 Hz, Ar-H), 9.84 (1H, s, CHO) ppm.
