Stabile Salze heteroleptischer Eisen‐Carbonyl/Nitrosylkationen

Abstract

Die Oxidation von Fe(CO)5 mit dem [NO]+‐Salz des schwach koordinierenden Perfluoroalkoxyaluminat‐Anions [F‐{Al(ORF)3}2]− (RF=C(CF3)3) führt zu stabilen Salzen der 18‐Valenzelektronenspezies [Fe(CO)4(NO)]+ und [Fe(CO)(NO)3]+ mit den Enemark‐Feltham‐Zahlen {FeNO}8 und {FeNO}10. Dies schließt 80 Jahre nach der Entdeckung der anionischen ([Fe(CO)3(NO)]−)‐ und neutralen ([Fe(CO)2(NO)2])‐Spezies endlich die bisherige Lücke in der Triade der heteroleptischen Eisen‐Carbonyl/Nitrosylkomplexe. Beide Salze wurden vollständig charakterisiert (IR, Raman, NMR, UV/Vis, scXRD, pXRD) und sind unter Inertbedingungen bei Raumtemperatur über Monate hinweg stabil. Sie können als nützliche Ausgangsmaterialien für weitergehende Untersuchungen dienen.

Chasing the Mond Cation: Synthesis and Characterization of the Homoleptic Nickel Tetracarbonyl Cation and its Tricarbonyl‐Nitrosyl Analogue

“…Note that already ortho ‐difluorobenzene has the potential to displace CO from the metal in TMCCs [26, 29] . For the oxidation to the target cation we tested Ag + and NO + salts that may react innocent by formation of TMCCs, [23, 26] but also non‐innocent by formation of Ag‐ or NO‐complexes [20, 30, 31] . Thus, the synergistic Ag + /0.5 I 2 system, [32, 33] reported to be more suitable for the generation of novel TMCCs, [20] with a high redox potential of about 1.49 V vs. SHE in water was used [33] .…”

“…[26,29] For the oxidation to the target cation we tested Ag + and NO + salts that may react innocent by formation of TMCCs, [23,26] but also non-innocent by formation of Ag-or NO-complexes. [20,30,31] Thus, the synergistic Ag + /0.5 I 2 system, [32,33] reported to be more suitable for the generation of novel TMCCs, [20] with a high redox potential of about 1.49 V vs. SHE in water was used. [33] Due to the high toxicity and volatility of neutral Ni(CO) 4 , we decided to use elemental nickel powder [34] as the starting material and converted it in CO atmosphere with the selected oxidizers to obtain the target cation [Ni(CO) 4 ]C + .…”

Bonding in PdCl(NO) and Related Nitrosylmetal Species of the Enemark–Feltham {MNO}10Type

“…Examples of halogenidonitrosyls include the mononuclear {M(NO) 3 } 10 trinitrosyls [FeBr(NO) 3 ] and [FeI(NO) 3 ], and the coordination polymer [{Co(μ‐I)(NO) 2 } n / n ] with infinite Co−I‐bonded chains and linear CoNO functions [10] . Related mononuclear mixed carbonyl‐nitrosyl species are typical text‐book examples such as the triad of T ‐4 species [Fe(CO) 3 (NO)] − , [Fe(CO) 2 (NO) 2 ] and [Fe(CO)(NO) 3 ] + [11] . The dinitrosyl is also part of the tetrad [Cr(NO) 4 ], [Mn(CO)(NO) 3 ], [Fe(CO) 2 (NO) 2 ] and [Co(CO) 3 (NO)] which collects tetrahedral nitrosyl complexes that are isosteric with the group‐10 carbonyl [Ni(CO) 4 ] [12] .…”

Chasing the Mond Cation: Synthesis and Characterization of the Homoleptic Nickel Tetracarbonyl Cation and its Tricarbonyl‐Nitrosyl Analogue

“…[26,29] For the oxidation to the target cation we tested Ag + and NO + salts that may react innocent by formation of TMCCs, [23,26] but also non-innocent by formation of Ag-or NO-complexes. [20,30,31] Thus, the synergistic Ag + /0.5 I 2 system, [32,33] reported to be more suitable for the generation of novel TMCCs, [20] with a high redox potential of about 1.49 V vs. SHE in water was used. [33] Due to the high toxicity and volatility of neutral Ni(CO) 4 , we decided to use elemental nickel powder [34] as the starting material and converted it in CO atmosphere with the selected oxidizers to obtain the target cation [Ni(CO) 4 ]C + .…”

“…Product 1 is isomorphous and isoelectronic to earlier reported [Mn(NO) 4 ] + [39] and [Fe(CO)(NO) 3 ] + salts. [31] Their almost linear M-C-O/M-N-O units (176 to 1798) are described in terms of the Enemark-Feltham notation [40] as {MNO} 10 .…”