Systematics of the Formation of Π-CO Ligands in Four-Iron Clusters. Synthesis and Structures of *CH2Cl2, Fe4(AuPet3)(CO)12(COCH3), , and

Article abstract of DOI:10.1021/ja00312a055

The Lewis acid ligands (1+), (1+), and (1+) interact with the metal framework of the tetrahedral iron cluster (2-).In all cases, two products result, one of which consists of the Fe4 tetrahedron with the Lewis acid capping one face.The other more novel product is a Fe4 butterfly array with the Lewis acid ligand on the hinge and a Π-CO between the wingtips.By proper choice of counterion and conditions, either the butterfly or tetrahedral form can be crystallized.X-ray structures were determined for representative compounds of both products in this series.Tetrahedral iron frameworks were observed for (5a) and (6(tetrahedron)).Both *CH2Cl2 (3a) and Fe4(AuPEt3)(CO)12(COCH3) (7) have butterfly iron cores.Butterfly complexes such as 3a display a characteristic and unique low-frequency Π-CO stretch in the 1380-1430-cm^-1 region of the IR spectrum.Additionally, NMR spectra of the individual isomers were obtained by dissolving the pure crystalline material at -80 deg C and obtaining the spectrum at this temperature.The NMR spectra obtained in this manner were consistent with both IR spectra of the solid and the structure determined by X-ray crystallography.

Full text of DOI:10.1021/ja00312a055

Evaluation Only. Created with Aspose.PDF. Copyright 2002-2021 Aspose Pty Ltd.

Evaluation Only. Created with Aspose.PDF. Copyright 2002-2021 Aspose Pty Ltd.

Evaluation Only. Created with Aspose.PDF. Copyright 2002-2021 Aspose Pty Ltd.

Evaluation Only. Created with Aspose.PDF. Copyright 2002-2021 Aspose Pty Ltd.