Synthesis of 1,2,3,4,5,6-hexakis (σ-methylene) benzene compounds of iron and cobalt carbonyls &their facile conversion into π-compounds

Abstract

The complexes 1,2,3,4,5,6-hexakis (σ-methylene) benzenedodecacarbonyltriiron (<strong>1</strong>) and 1,2,3,4,5,6- hexakis (σ-methylene tetracarbonylcobalt) benzene (<strong>3</strong>) have been synthesized by the reactions of 1,2,3,4,5,6-hexakis (bromomethyl)benzene with disodium tetracarbonylferrate and sodium tetracarbonylcobaltate, respectively. Complex <strong>1</strong> undergoes facile conversion into complex (<strong>2</strong>) where a a to π-conversion occurs with three Fe(CO)₃ moieties separately coordinated to three butadiene fragments. Attempts to convert complex (<strong>3</strong>) into π-form are, however, unsuccessful.