Radial (tetracyclopentadienyl)cyclobutadiene pentametals have been synthesized by the Pd-catalyzed coupling of cyclopentadienyltin or of (CpM)zinc reagents with (tetraiodocyclobutadiene)iron(tricabonyl). X-ray structural and NMR data reveal that, while these arrays are crowded, the substituents enjoy considerable rotational freedom.The method constitutes a significant complement to currently existing strategies for the construction of persubstituted cyclobutadiene complexes. (C) 2010 Elsevier B.V. All rights reserved.
Radial (tetracyclopentadienyl)cyclobutadiene pentametals have been synthesized by the Pd-catalyzed coupling of cyclopentadienyltin or of (CpM)zinc reagents with (tetraiodocyclobutadiene)iron(tricabonyl). X-ray structural and NMR data reveal that, while these arrays are crowded, the substituents enjoy considerable rotational freedom.The method constitutes a significant complement to currently existing strategies for the construction of persubstituted cyclobutadiene complexes. (C) 2010 Elsevier B.V. All rights reserved.