Phosphadicarbaborane Analogues of Ferrocene: New Isomers of [closo-(η5-C5H5)FePC2B8H10]

✍ Scribed by Bohumil Štíbr; Josef Holub; Mario Bakardjiev; Ivan Pavlík; Oleg L. Tok; Bernd Wrackmeyer

• Book ID: 102168948
• Publisher: John Wiley and Sons
• Year: 2003
• Tongue: English
• Weight: 122 KB
• Volume: 2003
• Category: Article
• ISSN: 1434-1948
• DOI: 10.1002/ejic.200300002

✦ Synopsis

Abstract

Thermal isomerisation of the ferraphosphadicarbaborane [1‐Cp‐closo‐1,2,4,5‐FePC~2~B~8~H~10~] (1a; Cp = η^5^‐C~5~H~5~^−^) at elevated temperatures (180−350 °C) leads to the formation of three new isomeric complexes. These were characterized by multinuclear (^1^H, ^11^B, ^31^P, and ^13^C) NMR spectroscopy and mass spectrometry as [1‐Cp‐closo‐1,2,3,8‐FePC~2~B~8~H~10~] (1b), [1‐Cp‐closo‐1,10,2,4‐FePC~2~B~8~H~10~] (1c), and closo‐[1,2,4,10‐FePC~2~B~8~H~10~] (1d). The formation of 1b is accompanied by an unusual agglomeration of the P and C heteroatoms. Complexes 1b and 1c have also been isolated as side products from the direct reaction between nido‐[7,8,9‐PC~2~B~8~H~11~] (2) and [CpFe(CO)~2~]~2~ in refluxing mesitylene, and 1a and 1b from the pyrolysis of [7‐Fp‐(η^1^‐nido‐7,9,10‐PC~2~B~8~H~10~)] [3; Fp = CpFe(CO)~2~] at 350 °C. NMR intercomparisons of all five [1‐Cp‐closo‐FePC~2~B~8~H~10~] isomers thus far isolated have been made. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)