Light-induced self-assemblies suitable for photodimerization and their light-induced [2+2] cycloaddition: Light as a control factor of crystal growth

► The reaction of Cd(NO3)2 and CF3COONH4 with bpe produced three coordination polymers under the light. ► Three compounds gradually underwent [2+2] cycloaddition to the product containing rctt-tpcb in light. ► The [2+2] cycloaddition reaction progress was monitored by fluorescent spectroscopy.