Benzil

Benzil is the organic compound with the formula (C6H5CO)2, generally abbreviated (PhCO)2. This diketone is used as an intermediate in organic synthesis. Benzil is also employed as a photoinitiator for free-radical curing of polymer networks. Ultraviolet radiation decomposes benzil, creating free-radical species which propagate throughout polymer material, creating cross-links between individual polymer chains. Recently benzil has been identified as a selective inhibitor of carboxylesterase enzymes, proteins involved in the metabolism of esterified drugs and xenobiotics.

Benzil can be prepared in the laboratory by the benzoin condensation of benzaldehyde followed by oxidation of benzoin using copper sulfate.
 * PhC(O)CH(OH)Ph +  2 Cu2+  &rarr;  PhC(O)C(O)Ph  +  2 H+  + 2 Cu+

A classical organic reaction of benzil is the Benzilic acid rearrangement to benzilic acid.