Solid-state photolysis of α-azidoacetophenones

Solid-state photolysis of 1 yields 2 in a crystal-to-crystal reaction. The reaction takes place by alpha-cleavage to form a benzoyl and an azido alkyl radical pair. The azido alkyl radicals rearrange into iminyl radicals and N-2. The iminyl and benzoyl radicals are held in close proximity within the crystal lattice, which allows them to combine and form 2. X-ray structure analysis, molecular modeling and trapping studies support this mechanism.