Diphenyl ethyl diketone, also known as bibenzoyl, benzoyl, bibenzoyl, dibenzoyl, chemical formula (C6H5CO)2, often abbreviated as (PhCO)2. A diketone used as an intermediate in organic synthesis. Under ultraviolet irradiation, diphenyl ethyl diketone is cracked into free radicals, which causes cross-linking between polymer chains and is therefore used as a photoinitiator in the solidification of polymers. Recent studies have shown that diphenyl ethyl diketone is a selective inhibitor of carboxylesterase. In the laboratory, diphenyl ethyl diketone can be prepared by condensation of benzoin from benzaldehyde, and then oxidized by copper sulfate to obtain:

PhC(O)CH(OH)Ph + 2 Cu2+ → PhC(O)C(O)Ph + 2 H+ + 2 Cu+

Under alkaline condition, diphenyl ethyl diketone is rearranged by dibenzoic acid and acidified to obtain dibenzoic acid.

Appearance and properties: yellow crystal

Density: 1,521 g/cm3

Boiling point: 346 °C

Melting point: 94-95 °C(lit.)

Flash point: 346-348°C

Refractive index: 1.594

Water solubility: 0.5g /L (20 oC)

Stability: Stable. Combustible. Incompatible with strong oxidizing agents.

Storage conditions: ventilation and dry at low temperature

Vapor pressure: 5.54E-05mmHg at 25°C

Usage

1. Organic synthesis. Insecticide. Used as a photocuring agent for photosensitive adhesives and photocuring coatings.

2. Used as pharmaceutical intermediates.