T=190°C;

in benzene byproducts: CO; addn. of 0.02 mol cis-3,4-dichlorocyclobutene and 0.05 mol iron nonacarbonyl to distilled benzene in round bottom flask under inert atmosphere; refluxing at 55°C with continous stirring for 1.5 h; filtration;; washing residue with pentane; removing solvent by evapn. under vacuum; distillation under vacuum; obtained as oil containing cyclobutadiene iron tricarbonyl, iron pentacarbonyl and triirondodecacarbonyl;;

in benzene byproducts: CO; addn. of 0.02 mol cis-3,4-dichlorocyclobutene and 0.05 mol iron nonacarbonyl to distilled benzene in round bottom flask under inert atmosphere; refluxing at 55°C with continous stirring for 1.5 h; filtration;; washing residue with pentane; removing solvent by evapn. under vacuum; distillation under vacuum; obtained as oil containing cyclobutadiene iron tricarbonyl, iron pentacarbonyl and triirondodecacarbonyl;;

in various solvent(s) T=180°C; 36 h;

Irradiation; Product distribution;