4,4'-Dihydroxy diphenyl sulfide is an aromatic di-thio-phenol in which hydroxyl groups are located para to the sulfur bridge on both benzene rings. The compound is air-stable in the solid state, freely soluble in acetone, ethanol, ethyl acetate and hot water, and sparingly soluble in cold water.
Key physicochemical data:
Melting point: 154–156 °C
Predicted boiling point: 389 °C at 760 mmHg
Predicted density: 1.32 g cm⁻³
pKa (phenolic): ~9.2
Log P (octanol/water): 1.9 (predicted)
Typical uses:
Antioxidant and thermal stabiliser for polyesters, polycarbonates and lubricants.
Building block for 4,4'-dihydroxy-diphenyl sulfoxide/sulfone high-performance epoxy hardeners and flame retardants.
Model substrate for mechanistic studies on phenolic C–O and C–S bond activation and cross-coupling reactions.
Quality specification (commercial grade):
Purity (HPLC): ≥98 %
Water content (KF): ≤0.3 %
Residue on ignition: ≤0.1 %
Heavy metals: ≤20 ppm
Hazard statement:
Causes skin and eye irritation (R36/37/38). Harmful if swallowed (R22). Avoid inhalation of dust; use gloves, goggles and adequate ventilation. Store in a cool, dry place away from oxidants. SDS available on request.
