The synthesis of bimetallic manganese tricarbonyl-capped metallocenes

Abstract

Stable bimetallic 'capped' metallocenes are formed by the reaction of Cp* 2 M (M = Fe, Ru, Os) with the manganese tricarbonyl transfer reagent [(h 6 -naphthalene)Mn(CO) 3 ] + .

Synthesis and Structures of Triple-Decker Complexes with a Bridging Tetramethylcyclopentadienyl Ligand

“…Although initial attempts to grow crystals of [Cp*Fe(μ-Cp*)Mn(CO) 3 ]BF 4 were not successful, recent experiments afforded green crystals of 1•PF 6 suitable for X-ray analysis. 21 As shown in Figure 1, the structure of 1 confirms the coordination of the [Mn(CO) 3 ] + fragment to a Cp* ring of decamethylferrocene and reveals that the manganese tricarbonyl stacked metallocene contains two perfectly staggered Cp* rings. Similarly, the two Cp* rings in free decamethylferrocene adopt a staggered conformation in the solid state.…”

“…17−20 As a unique example of the latter, Sweigart et al prepared unsymmetrical triple-layer complexes of the iron group by the electrophilic addition of the [Mn(CO) 3 ] + moiety to a Cp* ring of decamethylmetallocenes of Fe, Ru, and Os. 21 As shown in Scheme 1, the electron-rich Cp* 2 Fe displaced the labile acenaphthene ligand from [(η 6 -acenaphthene)Mn(CO) 3 ]BF 4 , affording the triple-layer complex [Cp*Fe(μ-Cp*)Mn(CO) 3 ]-BF 4 (1•BF 4 ). 22,23 The chemistry shown in Scheme 1 is an example of an "electrophilic stacking reaction" in which a coordinatively unsaturated metal complex fragment adds to a nucleophilic sandwich complex, producing a cationic triple-decker complex.…”

Triple-decker transition metal complexes bridged by a single carbocyclic ring

“…The synthesis of these complexes relies on the forward direction of reaction (1) (electrophilic stacking), but their stability is limited by the reverse reaction (nucleophilic degradation). For heterobimetallic triple-decker complexes, two regiochemistries are possible for the reverse reaction and equilibrium (2) [66]. All other complexes of this type are bridged by a heterocycle, usually a borole-based system.…”

Syntheses, Structures, and Mössbauer Effect Spectroscopy of Triple-Decker Complexes Incorporating Nonamethylferrocene

“…13−15 In 2001, Sweigart et al showed that [(η 6 -acenaphthene)Mn-(CO) 3 ]BF 4 transferred the manganese tricarbonyl cation [Mn(CO) 3 ] + to decamethylferrocene, producing the heterometallic triple-layer complex [Cp*FeCp*Mn(CO) 3 ]BF 4 . 16,17 In 2013, extension of this methodology to 1,2,3,4,1′,2′,3′,4′octamethylferrocene did not afford the expected Fe−Mn product [Cp′FeCp′Mn(CO) 3 ]BF 4 but instead produced the homometallic triple-decker complex [Cp′FeCp′FeCp′]BF 4 via ring abstraction and subsequent electrophilic addition. 18 Comparison of these two reactions in Scheme 1 reveals that a minor difference in the degree of ring alkylation (C 5 Me 5 vs C 5 Me 4 H) brought about a major difference in product formation.…”