Boryl and Bridged Borylene Complexes of Iron and Ruthenium

Abstract

The reactivity of aminodihaloboranes R 2 NBX 2 (R = Me, be isolated from these mixtures as pure materials. In addition the novel boryl and borylene ruthenium complexes [(η 5 -SiMe 3 ; X = Cl, Br) towards transition metal complexes of the type Na[(η 5 -C 5 RЈ 5 )M(CO) 2 )] (M = Fe, Ru; RЈ = H, Me) was C 5 H 5 )(CO) 2 Ru{BX(NMe 2 )}] (X = Cl 12a; X = Br 12b), [(η 5 -C 5 H 5 )(CO) 2 Ru{BCl{NSiMe 3 {BClN(SiMe 3 ) 2 }}}] (13) and [µ-investigated. In the case of Me 2 NBBr 2 and M = Fe the borylcomplexes [(η 5 -C 5 RЈ 5 )(CO) 2 Fe{BBr(NMe 2 )}] (C 5 RЈ 5 = BN(SiMe 3 ) 2 (µ-CO){(η 5 -C 5 H 5 )Ru(CO)} 2 ] (14) were obtained by similar methods. All compounds were characterized by C 5 H 5 9a; C 5 RЈ 5 = C 5 H 4 Me 9b; C 5 RЈ 5 = C 5 Me 5 10) were obtained. The compounds 9a and 9b were formed together multinuclear NMR and IR spectroscopy. The structure of 13 in the solid state was determined by a single-crystal X-ray with the corresponding bridged borylene complexes [µ-BNMe 2 (µ-CO){(η 5 -C 5 RЈ 5 )Fe(CO)} 2 ] (C 5 RЈ 5 = C 5 H 5 11a; diffraction study. C 5 RЈ 5 = C 5 H 4 Me 11b) in a 1:1 ratio, the latter, however, could C 5 RЈ 5 )Fe(CO)} 2 ] (C 5 RЈ 5 ϭ C 5 H 5 3a; C 5 RЈ 5 ϭ C 5 H 4 Me 3b) [b]

Transition‐Metal Complexes of Boron—New Insights and Novel Coordination Modes

“…Reactions of anionic cyclopentadienyl iron and ruthenium precursors with dimethylamino(dihalo)boranes afforded selective substitution of only one halide atoms to yield the corresponding amino(halo)boryl complexes 27 – 32 (Scheme ) 33a,b…”

“…A rather weak π interaction between the iron and boron atoms is indicated by low carbonyl stretching frequencies ($\tilde \nu $ =1988, 1928 cm −1 ) and by a rather large FeB bond length (2.027(5) Å). Reaction of the strong nucleophile Na[(η 5 ‐C 5 H 5 )Fe(CO) 2 ] with Me 2 NBBr 2 , however, produced a 1:1 mixture of the boryl complex [(η 5 ‐C 5 H 5 )Fe(CO) 2 {B(Br)NMe 2 }] ( 33 ) and the bridging borylene complex [(μ‐BNMe 2 )(μ‐CO){(η 5 ‐C 5 H 5 )Fe(CO)} 2 ] ( 34 , Scheme ) 33b…”

Übergangsmetallkomplexe des Bors – Neue Erkenntnisse und neuartige Koordinationstypen

“…Die Umsetzung von anionischen Cyclopentadienyleisen‐ oder Rutheniumvorstufen mit Dimethylamino(dihalogen)boranen geht mit der selektiven Substitution nur eines Halogenidliganden unter Bildung der Amino(halogen)borylkomplexe 27 – 32 einher (Schema 11) 33a,b…”

“…Die niedrigen $\tilde \nu $ ‐Werte für die Carbonylstreckschwingungen (1988, 1928 cm −1 ) und der große Fe‐B‐Abstand (2.027(5) Å) weisen auf eine schwache π‐Wechselwirkung zwischen Eisen und Bor hin. Das starke Nucleophil Na[(η 5 ‐C 5 H 5 )Fe(CO) 2 ] reagierte mit Me 2 NBBr 2 zu einem 1:1‐Gemisch aus dem Borylkomplex [(η 5 ‐C 5 H 5 )Fe(CO) 2 {B(Br)NMe 2 }] ( 33 ) und dem verbrückten Borylenkomplex [(μ‐BNMe 2 )(μ‐CO){(η 5 ‐C 5 H 5 )Fe(CO)} 2 ] ( 34 , Schema 12) 33b…”

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

“…[12,13] However, this method may have reached its limits, because it is restricted to a few specific combinations of transition metals and boranes. [14][15][16] More recently, we were able to show that photochemically induced borylene transfer is a valuable method for the synthesis of borylene complexes that cannot be obtained by salt elimination. [17,18] Furthermore, this approach allows the transfer of the borylene unit to organic substrates.…”