Reactivity of [M₂(μ‐Cl)₂(cod)₂] (M=Ir, Rh) and [Ru(Cl)₂(cod)(CH₃CN)₂] with Na[H₂B(bt)₂]: Formation of Agostic versus Borate Complexes

Abstract

Treatment of [M (μ-Cl) (cod) ] (M=Ir and Rh) with Na[H B(bt) ] (cod=1,5-cyclooctadiene and bt=2-mercaptobenzothiazolyl) at low temperature led to the formation of dimetallaheterocycles [(Mcod) (bt) ], 1 and 2 (1: M=Ir and 2: M=Rh) and a borate complex [Rh(cod){κ -S,S'-H B(bt) }], 3. Compounds 1 and 2 are structurally characterized metal analogues of 1,5-cyclooctadiene. Metal-metal bond distances of 3.6195(9) Å in 1 and 3.6749(9) Å in 2 are too long to consider as bonding. In an attempt to generate the Ru analogue of 1 and 2, that is [(Rucod) (bt) ], we have carried out the reaction of [Ru(Cl) (cod)(CH CN) ] with Na[H B(bt) ]. Interestingly, the reaction yielded agostic complexes [Ru(cod)L{κ -H,S,S'-H B(bt) }], 4 and 5 (4: L=Cl; 5: L=C H NS ). One of the key differences between 4 and 5 is the presence of different ancillary ligands at the metal center. The natural bond orbital (NBO) analysis of 1 and 2 shows that there is four lone pairs of electrons on each metal center with a significant amount of d character. Furthermore, the electronic structures and the bonding of these complexes have been established on the ground of quantum-chemical calculations. All of the new compounds were characterized by IR, H, B, C NMR spectroscopy, and X-ray crystallographic analysis.

Five‐Membered Ruthenacycles: Ligand‐Assisted Alkyne Insertion into 1,3‐N,S‐Chelated Ruthenium Borate Species

“…The torsion angle of the four‐membered Ru‐S‐C‐N ring for 2 a (2.2(4)°) is markedly larger than that for 2 b (−3.5(5)°). The Ru−B distance of 2.505(6) Å for 2 a is shorter than that for 2 b (2.554(9) Å) and other reported borate complexes, for example, [Cp*Ru{κ 3 ‐H,S,S ’ −H 2 B(L) 2 }] (2.753(1) Å) and [(cod)ClRu{κ 3 ‐H,S,S ’ −H 2 B(L) 2 }] (2.697(4) Å; cod=cyclooctadiene, L=C 7 H 4 NS 2 ) . In line with the substitution of R=Ph in 2 a to R=Cy in 2 b , the Ru−P distance is found to be longer in 2 b (2.3573(19) Å) than in 2 a (2.3124(13) Å).…”

“…The Ru1−S6 distance of 2.4741(18) Å in 2 a’ is significantly longer than the Ru1−S2 and Ru1−S4 distances in 2 a’ (2.3268(18) and 2.3469(16) Å respectively) and other ruthenium complexes . The Ru−B distance of 2.755 Å in 2 a’ is significantly longer than that of 2 a (2.505(6) Å) and [ClRu(cod){κ 3 ‐H,S,S’−H 2 B(mbz) 2 }] (2.697(3) Å) …”

Structure, electronic, inclusion complex formation behavior and spectral properties of pillarplex

“…Determining the NMR spectral properties with such level of theory becomes computationally demanding for large molecular systems. We therefore employ B3LYP functional, which has been widely used to study the metal complexes [45,46]. Table 5 Topological parameters obtained from AIM analysis for the DAO@ Au-Pillarplex ρ-Electron density (a.u.…”

Transition Metal Borate Complexes Containing κ0‐κ6 Denticity of Scorpionate Borate Ligands

“…[102] This synthetic approach has been capitalised to generate TM borate complexes by several groups including those of stradiotto, [105] Oestreich, [106] Wang, [107] Gessner [108] and us. [109][110] While exploring the reactivity of k 2 -N,S-chelated TM complexes towards various boranes, [109] [111] The presence of BÀ H terminal proton in 25 was indicated by the broad signals at δ = 8.03 and 3.98 ppm in the 11 B{ 1 H} and 1 H NMR spectra, respectively. The molecular structure of 25 displayed a k 2 -S,S-chelated ring in which the sulfur is coordinated to rhodium and nitrogen is coordinated to boron (Figure 12).…”