A bifunctional aromatic thiol bearing two ethoxy side-chains at the 2- and 5-positions. The strong electron-donating effect of the ethoxy groups raises the HOMO energy of the sulfur lone pair, giving a predicted pKₐ ≈ 6.4 and excellent nucleophilicity for metal-chelation, RAFT chain-transfer or thiol-ene click reactions. It is a key intermediate for:
High-refractive-index poly(aryl sulfide) optical resins (nD ≈ 1.68) used in 5G lens and OLED encapsulation films;
Electron-rich aryl-sulfide ligands in Cu- or Pd-catalysed cross-couplings and photoredox transformations;
Self-assembled monolayers (SAMs) on gold surfaces, providing hydrophobic yet polar surfaces for SERS sensors and MEMS anti-stiction layers;
Synthesis of 2,5-diethoxy-phenethyl thio-ethers employed as fragrance fixatives and antioxidant additives.
Store under nitrogen at 2–8 °C, protect from oxidants to prevent disulfide formation.
