Engineering Reactions in Crystalline Solids:  Radical Pairs in Crystals of Dialkyl 1,3-Acetonedicarboxylates

Crystalline dialkyl 1,3-acetonedicarboxylates give dialkyl succinates in high chemical yields by combination of alpha-carbonyl radical pairs produced by photochemical decarbonylation. It is proposed that the solid-state reaction depends on the exothermicity of two consecutive bond cleavage processes. It is also suggested that the efficiency of radical formation in the solid state is determined by the effect of substituents on bond dissociation energies and radical-stabilization abilities.