σ-Coordination of metal–boryl bonds to gold(i)

Abstract

The first examples of σ-coordinated metal-haloboryl complexes have been synthesised. The haloboryl moiety may be functionalized by nucleophilic substitution reactions, by which more electron-withdrawing substituents may be installed at the boron center.

Side-on coordination of boryl and borylene complexes to cationic coinage metal fragments

“… 14 , 23 The only localized BCPs were those for the Mn–B and M–B (M = Cu, Ag, Au) bonds. Similarly to the previously-reported gold boryl complex 2 , 13 , 14 the bond paths from the boron to the coinage metal cations in [ 8 ] + –[ 10 ] + are strongly bent towards the manganese atom, suggesting that the interactions between the boron and coinage-metal atoms are not covalent but rather σ-donation from π-orbitals of the manganese borylene unit. The valence shell charge concentration (VSCC) close to the boron atom is extended over both metal–boron BCPs (Mn–B and Au–B; see Fig.…”

“…Single-crystal X-ray diffraction studies have confirmed the structures of 5a and 5b to be [(η 5 -C 5 H 5 )(OC) 2 Mn{μ-B(R)( t Bu)}Au(PPh 3 )] (R = Ph, 5a and CCPh, 5b ), which are isostructural to 2 , apart from the second anionic substituent at boron. 13 The Mn–B bond distances of 5a and 5b are 2.156(3) and 2.157(9) Å, respectively, very similar to each other and both slightly longer than that observed in 2 (2.126(9) Å). Concurrently, the Au–B bond also elongates slightly upon halide replacement, exhibiting Au–B distances of 2.356(2) and 2.326(8) Å for 5a and 5b , respectively, compared to 2.303(9) Å of 2 .…”

“…Recently, we have communicated that the complex [(η 5 -C 5 H 5 )(OC) 2 Mn B t Bu] ( 1 ) reacted with gold( i ) chloride complexes to form heterodinuclear complexes [(η 5 -C 5 H 5 )(OC) 2 Mn{μ-B(Cl)( t Bu)}Au(L)] (L = PPh 3 , 2 ; PCy 3 , 3 ; ITol, 4 ; ITol = {C 3 N 2 H 2 (C 6 H 4 Me) 2 }), which are best viewed as σ-coordinated transition metal haloboryl complexes. 13 Among these, the reaction with AuCl(PPh 3 ) affords the best yield and therefore complex 2 has been used for subsequent studies ( Scheme 1 ).…”

“…This study reports the first bisborylene coinage metal complexes [{(η 5 -C 5 H 5 )(OC) 2 Mn} 2 {μ 2 -B( t Bu)} 2 M][BArx4] (M = Au, Ag and Cu; Ar x = C 6 H 3 Cl 2 , C 6 H 3 (CF 3 ) 2 ), 11 , 12 which formed from halide-abstraction reactions of the recently reported σ-coordinated boryl complex [(η 5 -C 5 H 5 )(OC) 2 Mn{μ-B(Cl)( t Bu)}Au(PPh 3 )] ( 2 ). 13 …”

Platinum Oxoboryl Complexes as Substrates for the Formation of 1:1, 1:2, and 2:1 Lewis Acid–Base Adducts and 1,2‐Dipolar Additions

“…2 Mn{m-B(SCN)(tBu)}Au(PPh 3 )] (28)a re the first exampleso ft ransition metal complexes in whichametal-coordinated boron atom bears an isothiocyanate group. [49] By diffusion of toluene into as olution mixture of benzene, hexanes, and dichloromethane, colorless crystals of trans-[(Cy 3 P) 2 BrPt{B(NCS)(OSiMe 3 )}] (27)s uitable for X-ray diffraction were formed (Figure 4). The platinum atom of 27 was found to be square-planar,b ound to an sp 2 -hybridized boryl ligand.…”