Isocyanid‐ und Heteroallen‐verbrückte Metallkomplexe, X. Protonierung und Alkylierung von (μ‐Acylisocyanid)‐ und (μ‐Iminoacylisocyanid)dieisen‐Komplexen

Isocyanide‐ and Heteroallene‐Bridged Metal Complexes, X [1,2] . – Protonation and Alkylation of (μ‐Acylisocyanide)‐ and (μ‐Iminoacylisocyanide)diiron Complexes Protonation of the acyl isocyanide‐bridged diiron complexes cis ‐[Fe 2 Cp 2 (CO) 3 (μ‐CNCOR)] [R = Ph ( 1a ); C 6 H 4 NO 2 ‐(4) ( 1b )] with HBF 4 or HPF 6 occurs at the isocyano nitrogen to give the cationic μ‐aminocarbyne complexes 2a and 2b , respectively. In contrast, the μ‐iminoacyl isocyanide complex 3 is both protonated and alkylated at the imino nitrogen. According to an X‐ray structure analysis of 4a , the resulting ligand systems in cis ‐[Fe 2 Cp 2 (CO) 3 {μ‐CNC(Ph)N(Ph)R}] + BF 4 + [R = H ( 4a ); Et ( 4b )] are best described as hybrids of μ‐2‐azaallylidene‐and μ‐2‐azaallenylidene‐type resonance structures.