Single-crystal to single-crystal transformation of a coordination chain to a two-dimensional coordination network through a photocycloaddition reaction

Irradiation of single crystals of a ladder-like coordination chain with 365 nm UV light induces a regiospecific photochemical [2 + 2] cycloaddition reaction of each pair of adjacent diolefinic ligands from neighbouring crystallographically equivalent chains and thus affords a two-dimensional (4,4)-connected coordination network through single-crystal to single-crystal transformation.