32545-54-3

Upstream product

• 67-56-1 methanol 
• 780-55-2 2-phenylheptamethyltrisilane 
• 1631-82-9 chloro(methyl)phenylsilane 
• 149-73-5 trimethyl orthoformate 
• 149-74-6 dichloromethylphenylsilane 
• 1192028-47-9 1,1,2,3,3-pentamethyl-2-phenyl-1,2,3-trisilacyclohexane 
• 1192028-48-0 1,1,2,3,3-pentamethyl-2-phenyl-1,2,3-trisilacycloheptane 
• 766-08-5 methylphenylsilane 
• 3027-21-2 dimethoxy(methyl)phenylsilane 
• 25015-63-8 4,4,5,5-tetramethyl-[1,3,2]-dioxaboralane 
• 75843-96-8 1-Phenylsilaethen 

Relevant academic research and scientific papers

Hydrosilane σ-Adduct Intermediates in an Adaptive Zinc-Catalyzed Cross-dehydrocoupling of Si?H and O?H Bonds

Three-coordinate PhBOX (Formula presented.) ZnR (PhBOX (Formula presented.) =phenyl-(4,4-dimethyl-oxazolinato; R=Me: 2 a, Et: 2 b) catalyzes the dehydrocoupling of primary or secondary silanes and alcohols to give silyl ethers and hydrogen, with high turnover numbers (TON; up to 107) under solvent-free conditions. Primary and secondary silanes react with small, medium, and large alcohols to give various degrees of substitution, from mono- to tri-alkoxylation, whereas tri-substituted silanes do not react with MeOH under these conditions. The effect of coordinative unsaturation on the behavior of the Zn catalyst is revealed through a dramatic variation of both rate law and experimental rate constants, which depend on the concentrations of both the alcohol and hydrosilane reactants. That is, the catalyst adapts its mechanism to access the most facile and efficient conversion. In particular, either alcohol or hydrosilane binds to the open coordination site on the PhBOX (Formula presented.) ZnOR catalyst to form a PhBOX (Formula presented.) ZnOR(HOR) complex under one set of conditions or an unprecedented σ-adduct PhBOX (Formula presented.) ZnOR(H?SiR′3) under other conditions. Saturation kinetics provide evidence for the latter species, in support of the hypothesis that σ-bond metathesis reactions involving four-centered electrocyclic 2σ–2σ transition states are preceded by σ-adducts.

Seeking Heteroatom-Rich Compounds: Synthetic and Mechanistic Studies into Iron Catalyzed Dehydrocoupling of Silanes

A detailed synthetic investigation into the dehydrocoupling of silanes with amines, phosphines, and alcohols using an iron precatalyst (1) is presented. We have furnished over 30 examples of aminosilane synthesis along with kinetic studies using MeBnNH and MePhSiH2 as coupling partners. The kinetic studies suggest a reversible reaction with silane which generates aminosilane and an Fe-hydride dimer that undergoes rate-limiting protonolysis with amine with N-H bond cleavage in the transition state, consistent with a primary KIE of 2.42(3). The presence of dimers as on-cycle intermediates was analyzed in depth. Beyond this we have explored the substrate scope of phosphinosilane formation which shows a preferential heterodehydrocoupling to give the phosphinosilane with primary and secondary silanes. Silylethers can also be prepared and alcohols that contain alkene functionality do not show any tendency to reduce the double bond.

Synthesis of hydrosilanes: Via Lewis-base-catalysed reduction of alkoxy silanes with NaBH4

Hydrosilanes were synthesized by reduction of alkoxy silanes with BH3 in the presence of hexamethylphosphoric triamide (HMPA) as a Lewis-base catalyst. The reaction was also achieved using an inexpensive and easily handled hydride source NaBH4, which reacted with EtBr as a sacrificial reagent to form BH3in situ.

Catalytic Reduction of Alkoxysilanes with Borane Using a Metallocene-Type Yttrium Complex

The catalytic reduction of alkoxysilanes with the borane HBpin (pin = pinacolato) was achieved using a metallocene-type yttrium complex as a catalyst precursor. Mechanistic study supported the pivotal role of the rigid metallocene structure of the catalyst, which bears two bulky n5-C5Me4SiMe3 ligands, in suppressing the coordination of the side product MeOBpin that is generated during the reaction.

Platinum-Catalyzed Multicomponent Alcoholysis/Hydrosilylation and Bis-hydrosilylation of Alkynes with Dihydrosilanes

A new method for the hydrosilylation of alkynes controlled by a platinum catalyst with a monophosphine ligand (called TBSO-MOP) was explored. The platinum-catalyzed multicomponent and sequential silylation reaction involving alkynes, alcohols, and dihydrosilanes resulted in the highly stereoselective and high-yielding construction of functional (E)-vinylsilyl ethers. Moreover, the one-pot bis-hydrosilylation of terminal alkynes with dihydrosilanes was also achieved with the same platinum catalyst system.

Photochemistry of cyclic trisilanes: "Spring-loaded" precursors to methylphenylsilylene

Two new cyclic trisilanes containing a SiMePh moiety in the central position have been synthesized, and their photochemistries studied by steady-state and laser flash photolysis methods. The yield of the transient silylene SiMePh increases at the expense

Steady state and time-resolved spectroscopic studies of the photochemistry of 1-arylsilacyclobutanes and the chemistry of 1-arylsilenes

Direct photolysis of 1-phenylsilacyclobutane and 1-phenyl-, 1-(2-phenylethynyl)-, and 1-(4'-biphenylyl)-1-methylsilacyclobutane in hexane solution leads to the formation of ethylene and the corresponding 1-arylsilenes, which have been trapped by photolysis in the presence of methanol. Quantum yields for photolysis of the three methyl-substituted compounds have been determined to be 0.04, 0.26, and 0.29, respectively, using the photolysis of 1,1-diphenylsilacyclobutane (Φ(silene) = 0.21) as the actinometer. The corresponding silenes have been detected by laser flash photolysis; they have lifetimes of several microseconds, exhibit UV absorption maxima ranging from 315 to 330 nm, and react with methanol with rate constants on the order of (2-5) x 109 M-1 s-1 in hexane. Absolute rate constants for reaction of 1-phenylsilene and 1-methyl-1-phenylsilene with water, methanol, tert-butanol, and acetic acid in acetonitrile solution have been determined, and are compared to those of 1,1-diphenylsilene under the same conditions. With the phenylethynyl- and biphenyl-substituted methylsilacyclobutanes, the triplet states can also be detected by laser flash photolysis, and are shown to not be involved in silene formation on the basis of triplet sensitization and (or) quenching experiments. Fluorescence emission spectra and singlet lifetimes have been determined for the three 1-aryl-1-methylsilacyclobutanes, 1,1-diphenylsilacyclobutane, and a series of acyclic arylmethylsilane model compounds. These data, along with the reaction quantum yields, allow estimates to be made of the rate constants for the excited singlet state reaction responsible for silene formation. 1-Methyl-1-phenylsilacyclobutane undergoes reaction from its lowest excited singlet state with a rate constant 10-80 times lower than those of the other three derivatives. The results are consistent with a stepwise mechanism for silene formation, involving a 1,4-biradicaloid intermediate that partitions between product and starting material.

Separation of chiral silicon compounds using permethylated α-, β-, and γ-cyclodextrin capillary GC columns

Permethylated α-, β-, and γ-cyclodextrin GC stationary phases were used to resolve racemic silane derivatives, R1R2Si*PhMe. Particularly good resolutions were obtained on the β-CD phase for racemates containing a silanol g

υ-Ray- and UV-induced Generation of Methyl(phenyl)silylene and Silene Species from Heptamethyl-2-phenyltrisilane

A benzene solution of heptamethyl-2-phenyltrisilane (1) has been irradiated with γ-rays in the presence of methanol.Hexamethyldisilane, methoxymethyl(phenyl)silane (2) and a 1-methoxytetramethyldisilanyl- and trimethylsilyl-substituted cyclohexadiene (3) were produced.The formation of 2 and 3 can be interpreted in terms of reactions of methanol with methyl(phenyl)silylene and a silicon-carbon double-bonded intermediate (silene), respectively.These intermediates are generated as follows.Benzene is first excited by γ-rays and by collisions the energy transfers to 1.Excited 1 decomposes to give methyl(phenyl)silylene or undergoes rearrangement to a silene intermediate as when 1 is excited by UV light.A kinetic study revealed that the energy transfer in the γ-irradiated system is the same as that in a UV-irradiated system.