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• 617-86-7 triethylsilane 
• 4467-06-5 2-(4-methylphenyl)pyridine 

Relevant academic research and scientific papers

An effective and versatile strategy for the synthesis of structurally diverse heteroarylsilanesviaIr(iii)-catalyzed C-H silylation

A versatile silylation of heteroaryl C-H bonds is accomplished under the catalysis of a well-defined spirocyclic NHC Ir(iii) complex (SNIr), generating a variety of heteroarylsilanes. A significant advantage of this catalytic system is that multiple types of intermolecular C-H silylation can be achieved using one catalytic system at α, β, γ, or δ positions of heteroatoms with excellent regioselectivities. Mechanistic experiments and DFT calculations indicate that the polycyclic ligand of SNIr can form an isolable cyclometalated intermediate, which leaves a phenyl dentate free and provides a hemi-open space for activating substrates. In general, favorable silylations occur at γ or δ positions of chelating heteroatoms, forming 5- or 6-membered C-Ir-N cyclic intermediates. If such an activation mode is prohibited sterically, silylations would take place at the α or β positions. The mechanistic studies would be helpful for further explaining the reactivity of the SNIr system.

Ruthenium(ii)/acetate catalyzed intermolecular dehydrogenative: Ortho C-H silylation of 2-aryl N-containing heterocycles

The first application of a RuHCl(CO)(PPh3)3-OAc catalytic system on the selective intermolecular mono C-H silylation of 2-aryl N-heterocycles using HSiEt3 as the silylating reagent has been described. This protocol features good functional group tolerance and high regioselectivity, and has potential for gram scale-up, which provides a convenient and practical pathway for the synthesis of versatile organosilane compounds. This catalytic system can also be applied to the silylation of challenging sp3 C-H bonds.

Synthetic method for 2-aryl ortho-substituted triethylsilyl pyridine compound

The invention discloses a synthetic method for a 2-aryl ortho-substituted triethylsilyl pyridine compound. The method includes the following steps: adding triethylsilane, a 2-aryl pyridine compound, inorganic base, unsaturated olefin and a ruthenium catal

A well-defined NHC-Ir(III) catalyst for the silylation of aromatic C-H bonds: Substrate survey and mechanistic insights

A well-defined NHC-Ir(iii) catalyst, [Ir(H)2(IPr)(py)3][BF4] (IPr = 1,3-bis-(2,6-diisopropylphenyl)imidazol-2-ylidene), that provides access to a wide range of aryl- and heteroaryl-silanes by intermolecular dehydrogenative C-H bond silylation has been prepared and fully characterized. The directed and non-directed functionalisation of C-H bonds has been accomplished successfully using an arene as the limiting reagent and a variety of hydrosilanes in excess, including Et3SiH, Ph2MeSiH, PhMe2SiH, Ph3SiH and (EtO)3SiH. Examples that show unexpected selectivity patterns that stem from the presence of aromatic substituents in hydrosilanes are also presented. The selective bisarylation of bis(hydrosilane)s by directed or non-directed silylation of C-H bonds is also reported herein. Theoretical calculations at the DFT level shed light on the intermediate species in the catalytic cycle and the role played by the ligand system on the Ir(iii)/Ir(i) mechanism.

Hemilabile N-Xylyl-N ′-methylperimidine carbene iridium complexes as catalysts for C-H activation and dehydrogenative silylation: Dual role of N-xylyl moiety for ortho-C-H bond activation and reductive bond cleavage

Direct dehydrogenative silylation of pyridyl and iminyl substrates with triethylsilane was achieved using (L)Ir(cod)(X) (1) (L = a perimidine-based carbene ligand, X = OAc and OCOPh) complexes as catalysts under toluene refluxing conditions in the presence of norbornene as a hydrogen scavenger, and the silylated products were obtained in good yields. The isolated bis(cyclometalated)iridium complexes, (CaC:)(C aN)IrOAc (2) (CaC: = a cyclometalated perimidine-carbene ligand and CaN = a cyclometalated pyridyl- and iminyl-ligated aromatic substrate), were key intermediates, where cyclometalated five-membered metallacycles of substrates such as phenylpyridine were selectively formed before yielding mono-ortho-silylation products. The bis(cyclometalated)iridium complex ( XyCaC:)(CaN)IrOAc (2d) (XyCaC: = a cyclometalated N-xylyl-N′-methylperimidine-carbene ligand and CaN = a 2-pyridylphenyl ligand), reacted with 2 equiv of Et3SiH to give an iridium hydride complex, (L4)(CaN)Ir(H) (SiEt3) (8d) (L4 = N-CH3, N-3,5-(CH 3)2C6H3 perimidine), via demetalation of a N-3,5-xylyl ring of the carbene ligand of 2d. The formation of 8d was confirmed by isolating the corresponding chloro complex (L 4)(CaN)Ir(Cl)(SiEt3) (8d-Cl) by treatment with CCl4. The N-methyl moiety of the carbene ligand coordinated to 8d was cyclometalated in the presence of norbornene at room temperature to afford (MeCaC:)(C aN)Ir(SiEt3) (10d) (MeC aC: = a cyclometalated N-xylyl-N′-methylperimidine- carbene), while at high temperature 8d reacted with norbornene and Et 3SiH to afford the silylated product, 2-(2-triethylsilyl) phenylpyridine (3a) and norbornane. A deuterium labeling experiment using 2d and Et3SiD (excess) revealed the incorporation of deuterium atoms at two ortho-positions of the N-xylyl group (>90%) and at the 3-position of 2-pyridylphenyl ligand (ca. 40%) within 3 h at room temperature, indicating that the cyclometalation/demetalation of the N-xylylperimidine carbene and 2-phenylpyridine ligands were reversible processes. Isolation of these cyclometalated iridium complexes under controlled conditions and D-labeling experiments thus revealed a dual function of the N-aryl group bound to the perimidine-carbene ligand, which acted as both a neutral carbene ligand and a monoanionic ortho-metalated aryl-carbene ligand through reversible C-H bond activation and Ir-C bond cleavage of the N-aryl group during the catalytic cycle.