Dibenzyl disulfide is the simplest aromatic–aliphatic disulfide, consisting of two benzyl groups linked by an –S–S– bridge. It is essentially odourless, stable under ambient conditions, freely soluble in hot ethanol, benzene, dichloromethane and mineral oils, and practically insoluble in water (< 0.1 g L⁻¹ at 25 °C). Commercial material is supplied ≥99 % pure.
Key physicochemical data:
Melting point: 71–74 °C
Boiling point: 270 °C / 20 mmHg; 356 °C / 760 mmHg (predicted)
Density: 1.15 g cm⁻³ (20 °C, solid)
Refractive index: 1.633 (70 °C, melt)
Flash point: 168 °C (closed cup)
Vapour pressure: <0.01 mmHg (25 °C)
Log P (octanol/water): 4.9 (predicted)
Typical uses:
High-temperature lubricant additive and extreme-pressure (EP) anti-wear agent for gear oils, greases and metal-working fluids.
Slow-release sulfur donor for vulcanising polar rubbers (NR, NBR) and for producing benzyl-based pharmaceutical intermediates.
Model substrate for mechanistic studies on C–S bond activation, radical thiol–disulfide exchange and benzyl-radical chemistry.
Quality specification (commercial grade):
Purity (GC): ≥99 % (dried basis)
Water content (KF): ≤0.2 %
Free thiol (as BnSH): ≤0.1 %
Residue on ignition: ≤0.1 %
Heavy metals: ≤20 ppm
Hazard statement:
Causes skin and eye irritation (H315 + H319). Avoid inhalation of dust; use gloves, goggles and adequate ventilation. Store in a cool, dry place away from oxidants and reducing agents. SDS available on request.
