Fe=B double bonds: Synthetic, structural, and reaction chemistry of cationic terminal borylene complexes

Journal article

Application of halide abstraction chemistry to asymmetric haloboryl complexes (η5-C5-Me5)Fe(CO) 2B(ERn)X leads to the first synthetic route to cationic multiply bonded group 13 diyl species, [(η5-C5Me 5)Fe(CO)2B(ERn]+. The roles of steric bulk and π electron release within the ERn substituent in generating tractable borylene complexes have been probed, as has the nature of the counterion. A combination of spectroscopic, structural, and computational techniques leads to the conclusion that the bonding in complexes such as [η5-C5Me5)Fe-(CO)2B(Mes)] + is best described as an Fe=B double bond composed of B→Fe σ donor and Fe→B π back-bonding components. An extended study of the fundamental reactivity of cationic borylene systems reveals that this is dominated not only by nucleophilic addition at boron but also by iron-centered substitution chemistry leading to overall displacement of the borylene ligand.

Authors: Coombs, D; Aldridge, S; Rossin, A; Jones, C; Willock, D

• Publication status: Published
• Journal: ORGANOMETALLICS
• Volume: 23
• Issue: 12
• Pages: 2911-2926
• Publication date: 2004-06-07
• DOI: 10.1021/om049793e
• EISSN: 1520-6041
• ISSN: 0276-7333
• Language: English