4,4'-Dihydroxy diphenyl disulfide is a bis-(p-hydroxyaryl) disulfide in which two phenol units are linked through sulfur atoms at the 4-position. The compound is air-stable, freely soluble in hot ethanol, methanol, aqueous alkali and DMF, moderately soluble in cold water, and practically insoluble in non-polar solvents. Commercial material is supplied ≥98 % pure.
Key physicochemical data:
Melting point: 208–211 °C (dec.)
Predicted b.p.: >450 °C (decomp.)
Density: 1.45 g cm⁻³ (20 °C, solid)
pKa (phenolic, 25 °C): ~9.2
Log P (octanol/water): 2.8 (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 (H315 + H319). 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.
