Reaktionen von MoNCl₃ und WNCl₃ mit elementarem Fluor. Kristallstrukturen von [MoO₂F₂(THF)₂] und [WF₄(NCl)(CH₃CN)]

Abstract

Die Nitridochloride MoNCl3 und WNCl3 reagieren ebenso wie WCl4(NCl) mit elementarem Fluor unter Bildung der N‐chlorimido‐Komplexe MoF4(NCl) und WF4(NCl), die durch ihre Spektren charakterisiert werden. Mit Tetrahydrofuran reagiert MoF4(NCl) unter Bildung von [MoF4(NCl)(THF)], das sich in THF‐Lösung langsam in MoO2F2(THF)2 umwandelt. WF4(NCl) bildet mit Acetonitril den Komplex [WF4(NCl)(CH3CN)]. Von beiden Donor‐Akzeptor‐Komplexen wurden Kristallstrukturanalysen angefertigt. [MoO2F2(THF)2]: Raumgruppe P21/n, Z = 4, Strukturlösung mit 1823 unabhängigen Reflexen, R = 0,033 für Reflexe mit I > 2σ(I). Gitterkonstanten bei −40°C: a = 636,2; b = 1119,5; c = 1625,2 pm; β = 93,92(1)º. Die Verbindung hat eine monomere Molekülstruktur, in der die F‐Atome in trans‐Position zueinander und die O‐Atome der THF‐Moleküle in trans‐Stellung zu den Oxoliganden angeordnet sind. [WF4(NCl)(CH3CN)]: Raumgruppe P21/m, Z = 2, Strukturlösung mit 1119 unabhängigen Reflexen, R = 0,038 für Reflexe mit I > 2σ(I). Gitterkonstanten bei 20°C: a = 511,7; b = 714,9; c = 1002,5 pm; β = 102,59(10)º. Die Verbindung hat eine monomere Molekülstruktur, in der das N‐Atom des Acetonitrilmoleküls in trans‐Stellung zur N‐chlorimido‐Gruppe WNCl angeordnet ist. Die Strukturparameter dieser Gruppe sind WN = 172,2 pm, NCl = 161,1 pm, WNCl 178,6º.

Medium and high oxidation state metal/non-metal fluoride and oxide–fluoride complexes with neutral donor ligands

“…219 The structure of [MoO 2 F 2 (thf) 2 ] obtained by decomposition of [MoF 4 (NCl)] in thf solution is similar. 222 The structure of the dinuclear [{MoO 2 F(2,2 0bipy)} 2 (m-O)] is also known. 221 The less studied [WO 2 F 2 (L) 2 ] (L = dmso, OPPh 3 , OPMe 3 ) are made by similar methods to the molybdenum analogues À either addition of L to a solution of ''tungstic acid'' (WO 3 ÁnH 2 O) in aqueous HF, or from [WO 2 Cl 2 (L) 2 ] and Me 3 SnF.…”

Synthesis, Characterization, and Lewis Acid Behavior of [W(NC6F5)F4]x and Computational Study of W(NR)F4 (R = H, F, CH3, CF3, C6H5, C6F5), W(NC6F5)F4(NCCH3), and W(NC6F5)F4(NC5H5)n (n = 1, 2)

“… a Calculated using the B3LYP functional with the Stuttgart basis set augmented by one f-type polarization function (W; α f = 0.823) and the cc-pVTZ (H, C, N, F) basis set. b From ref . c Defined as W–N(1)–Cl. …”

“…The Lewis acid and fluoride-ion acceptor behavior of analogous imido complexes (W­(NR)­F 4 ) is expected to be similar to that of WOF 4 and WSF 4 , which has been verified indirectly by the preparation of a number of alkylimido complexes such as W­(NR)­F 4 (NCCH 3 ) , and [RNH 3 ]­[W­(NR)­F 5 ], − as well as various [W­(NCl)­F 5 ] − , − [W­(NC 6 F 5 )­F 5 ] − , and [W 2 (NC 6 F 5 ) 2 F 9 ] − salts . However, to the best of our knowledge, the only definitive example of a direct Lewis acid–base reaction between W­(NR)­F 4 and a Lewis base is that of W­(NCl)­F 4 with CH 3 CN to afford monomeric W­(NCl)­F 4 (NCCH 3 ), whose crystal structure revealed a stereochemistry similar to that of the WChF 4 adducts . The parent compound was prepared by the direct fluorination of W­(NCl)­Cl 4 with F 2 .…”

Nitrido bridges between transition metals and main group elements illustrated by the series [M]NNa to [M]NCl

“…(39)] the chloro ligands bonded to the tungsten atom can be fluorinated, but not so the N-bonded chlorine atom. 60 Cl 4 W•N-Cl + 2 F 2 ? F 4 W•N-Cl + 2 Cl 2 (39) The high tendency for formation of the W•N-Cl group is also seen in the reaction of molybdenum and tungsten nitride chloride with elemental fluorine [eqn.…”