Synthesis of Trinuclear Heterobimetallic Cyanido‐Bridged Complexes from the Reaction of [Mn^I(CN)(CO)(tBuNC)₄] with Transition‐Metal Chlorides

Abstract

The reaction of [Mn(CN)(CO)(tBuNC)4] with MnCl2·4H2O, FeCl3·9H2O, NiCl2·6H2O, and CuCl2·2H2O, respectively, led to the formation of trinuclear heterobimetallic complexes that comprised two manganese moieties, with each coordinating the corresponding metal chloride entities through cyanide bridges. The mixed‐valence trinuclear MnI–CN–MnII–NC–MnI complex as well as the MnI–CN–NiII–NC–MnI derivative have been characterized by X‐ray structure analyses. In the case of the copper and iron compounds that exhibit easily reducable central metal ions, intramolecular electron transfer from manganese(I) to copper(II) or iron(III), respectively, is shown by the presence of metal‐to‐metal charge‐transfer (MMCT) bands as well as by EPR spectroscopy. Moreover, the iron complex shows a subsequent disproportionation, which was demonstrated by the isolation and crystallographic characterization of the reduced species with two manganese(I) complex units coordinating one FeIICl2 moiety.

Mixed-Isocyanide Complexes of Technetium under Steric and Electronic Control

“…Finally, the question of why the carbonyl ligands of compounds 2 are readily and completely replaced during reactions with CN p -FAr DarF2 and a mer -{Tc I (CN p -FAr DarF2 ) 3 } + core is formed, while no such reactions were observed for CN n Bu, CN t Bu, or CNCy remains. The fact that isocyanides should not be regarded as simple “CNR surrogates” of carbonyl ligands has been well accepted for a long time, and several examples of carbonyl/isocyanide exchange reactions have been reported. ,− In the chemistry of the group 7 elements, however, such replacements are mainly restricted to labilized carbonyl ligands. − ,,− The coordination properties of isocyanides are obviously governed by a complex interplay of their molecular orbitals. This results in substitution-specific and difficult-to-predict σ-donor and π-acceptor properties for the individual ligands, which may interfere additionally with restrictions given by the steric bulk of the residues .…”

Redox‐Assisted Self‐Assembly of a Water‐Soluble Cyanido‐Bridged Mixed Valence {CoIII/FeII}2 Square

“…Some seminal works exist that have proved to be the starting point for the better understanding of the intervalence charge transfer and the coupling established between the metal centers involved . Considerable research has been devoted to these compounds for a long time, but recently emphasis has shifted from simple dinuclear systems or non‐discrete complex materials to discrete homo‐ or heterosupramolecular species . The establishment of structure–property relationships for the latter, as well as their theoretical treatment, are facilitated by the fact that the structure is finite and the metal‐coordination environments are well defined.…”

“…[3,[5][6][7][8][9][10][11][12] Considerable research hasb een devoted to these compounds for al ong time, but recentlye mphasis has shifted from simple dinuclears ystems [4,[13][14][15][16][17][18][19][20][21][22] or non-discrete complex materials [13,[23][24][25][26][27] to discrete homo-or heterosupramolecular species. [16,[28][29][30][31][32][33][34][35][36][37] The establishmento fs tructure-property relationships for the latter,a sw ell as their theoretical treatment, are facilitated by the fact that the structure is finite and the metal-coordination environments are well defined. In particular,an umber of interesting examples of Prussian blue square complexes {Fe 2 Co 2 }h ave been reported, [34,[38][39][40][41][42][43][44][45][46]<...>…”