The Chemistry of Borylene Complexes

Abstract

Over the past seven years, complexes of various transition metals with bridged or terminal borylene ligands BR have for the first time been reported and fully characterised. Being closely related to important organometallic compounds, such as carbene, vinylidene, and carbonyl complexes, they have already attracted considerable interest both from experimental and computational points of view. Those studies have provided some detailed information about the nature of the

Borylentransfer unter thermischen Bedingungen: Synthese und Struktur eines Tetrarhodium‐Bisborylenkomplexes

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Wegen ihrer Verwandtschaft [1][2][3][4] zu Carbonyl-und Carbenkomplexen sowie ihres Potenzials, Borylene BÀR für organische Reaktionen zu liefern, [5] haben Übergangsmetall-borylenkomplexe großes Interesse geweckt. Trotz jüngster Erfolge bei der Verwirklichung neuartiger Koordinationsmodi in Metallborylenkomplexen [6,7] und Borylen-Heterozweikernkomplexen [8,9] sind die Möglichkeiten insofern immer noch stark eingeschränkt, als nur Kombinationen zwischen jeweils einem Borylenliganden und einem bzw.

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“…[19] Das Molekülgerüst besteht aus einer Kette von vier Rhodiumatomen; die beiden mittleren Rhodiumatome 4 ]. [20] Für diese Verbindung wie auch für Komplex 4 kann eine Rh-Rh-Bindung angenommen werden, wenn man die formal ungerade Elektronenzahl jedes Rhodiumatoms berücksichtigt.…”

Synthesis and Characterisation of Semi‐Bridging Molybdenum Borylene Complexes

“…Likewise, a variety of chromium borylene complexes were reported, e.g. [L(OC) 4 Cr=B=N(SiMe 3 ) 2 ] (L = CO, 1; PCy 3 , 10), [7,8a,9a,11b] [15] and in addition, one boryl complex [Cr(η 6 -C 6 H 6 )(CO) 2 (η 2 -tmpЈBCR 2 )] [tmpЈBCR 2 = (η 2 -9-fluorenylidene) (2,2,6,6-tertramethylpiperidino)-borane]. [19] In the case of molybdenum, however, only few boryl complexes of molybdenum are known, e.g.…”

“…[3] Borylene complexes as another type of metal-boron compound are also in the focus of research [4] because of their close relationship to carbonyl complexes and due to their propensity to effectively stabilise [4g,5] elusive borylenes [6] in the coordination sphere of a metal. In particular, group 6 transition metal carbonyl fragments have been shown to possess good stabilising properties resulting in the formation, by means of a salt elimination reaction, of [(OC) 5 M=B=N(SiMe 3 ) 2 ] (M = Cr, 1; W, 2) which are the first two-coordinate borylene complexes.…”

Borylene Transfer under Thermal Conditions: Synthesis and Structure of a Tetrarhodium Bisborylene Complex

“…The reaction of the terminal borylene complexes [(OC) 5 4 (m-CO)(CO) 4 ] (4; Scheme 1). After recrystallization in hexane, 4 was isolated as air-and moisture-sensitive black crystals in 43 % (M = Cr, 1) or 41% (M = W, 2) yield.…”