18758-54-8

Upstream product

• 76-86-8 Triphenylsilyl chloride 
• 98-85-1 1-Phenylethanol 
• 18758-49-1 1-phenyl-1-triphenylsilanyl-ethanol 
• 98-86-2 acetophenone 
• 789-25-3 HSiPh₃ 
• 1171-49-9 benzoyl-triphenyl-silane 

Downstream Products

• 1445-91-6 (S)-1-phenylethanol 
• 1517-69-7 (R)-1-phenylethanol 
• 17913-10-9 1-methyl-3-phenyl-butanal 

Relevant academic research and scientific papers

N-Heterocyclic Olefin Catalyzed Silylation and Hydrosilylation Reactions of Hydroxyl and Carbonyl Compounds

N-Heterocyclic olefins (NHOs), the alkylidene derivatives of N-heterocyclic carbenes (NHCs), have recently emerged as a new family of promising organocatalysts with strong nucleophilicity and Br?nsted basicity. The development of a novel method is shown using NHOs as efficient promoters for the direct dehydrogenative silylation of alcohols or hydrosilylation of carbonyl compounds. Preliminary results of the first NHO-promoted asymmetric synthesis are also discussed.

Exploring Multistep Continuous-Flow Hydrosilylation Reactions Catalyzed by Tris(pentafluorophenyl)borane

Exploring the combination of continuous-flow processes with the boron Lewis acid catalyzed hydrosilylation of aldehydes and ketones has delivered a robust and generally applicable reaction protocol. Notably this approach permits ready access to high temperatures and pressures and thus allows improved reactivity of substrates that were previously recalcitrant under the traditional approach. Efforts to quench the output from the flow reactor with water showed surprising tolerance leading to the application of continuous-flow systems in multistep imine formation/hydrosilylation processes to generate the corresponding secondary amines from their aldehyde and aniline precursors. (Figure presented.).

Iridacycles as Catalysts for the Autotandem Conversion of Nitriles into Amines by Hydrosilylation: Experimental Investigation and Scope

The set of iridacycles [{C,N}Cp?IrIII-Cl] ({C,N} = benzo[h]quinoline, dibenzo[f,h]quinoline) containing the (pentamethylcyclopentadienyl)iridium(III) unit were synthesized and derivatized into cations [{C,N}Cp?Ir-NCMe]+ associated wi

Hydrosilylation of various multiple bonds by a simple combined catalyst of a tungstate monomer and rhodium acetate

In the presence of a simple combined catalyst of a tungstate monomer (TBA2WO4, TBA: tetra-n-butylammonium) and rhodium acetate (Rh2(OAc)4), hydrosilylation of various types of substances including ketone, aldehyde, carbon dioxide, alkene, nitrile, and fur

Base-free dehydrogenative coupling of enolizable carbonyl compounds with silanes

A dehydrogenative coupling between enolizable carbonyl compounds and equimolar amounts of triorganosilanes catalyzed by a tethered ruthenium complex with a Ru-S bond is reported. The complex is assumed to fulfill a dual role by activating the Si-H bond to release a silicon electrophile and by abstracting an α-proton from the intermediate silylcarboxonium ion, only liberating dihydrogen as the sole byproduct. Reaction rates are exceedingly high at room temperature with very low loadings of the ruthenium catalyst.

InCl3/Me3SiBr-catalyzed direct coupling between silyl ethers and enol acetates

A combined Lewis acid catalyst of InCl3 and Me3SiBr promoted the direct use of enol acetates in the coupling with low-reactive silyl ethers, in which functional groups including ketones and aldehydes survived. Sterically hindered silyl ethers such as ROSiEt3, ROSiPh3, ROSit-BuMe2, and ROSii-Pr3 were also applicable.

Silylation-based kinetic resolution of monofunctional secondary alcohols

The nucleophilic small molecule catalyst (-)-tetramisole was found to catalyze the kinetic resolution of monofunctional secondary alcohols via enantioselective silylation. Optimization of this new methodology allows for selectivity factors up to 25 utilizing commercially available reagents and mild reaction conditions.

Analysis of the enantioselectivities and initial rates of the hydrosilylation of acetophenone catalyzed by [Rh(cod)Cl]2/(chiral diphosphine). The quantitative analysis of ligand effects

Through the application of the quantitative analysis of ligand effects (QALE) method to the study of the hydrosilylation of acetophenone, we have shown, for the first time, that the initial rate and enantioselectivity of a complicated catalytic system responds in a rational manner to the variations in the stereoelectronic properties of the silane. The reactions (in benzene-d6 at 63 °C) were catalyzed by [Rh(cod)Cl]2/(chiral diphosphine) (chiral diphosphine=(R)-BINAP [(R)-(+)-2,2′-bis(diphenylphosphino)- 1,1′binaphthyl], (R,R)-tolyl-BINAP [(R)-(+)-2,2′-bis (di-p-tolylphosphino)-1,1′-binaphthyl], (R,R)-Me-DUPHOS [(R,R )-(-)-1,2-Bis-2,5-dimethylphospholano)benzene], (R,R)-DIOP [(R,R)-(-)-2,3-O-isopropylidine-2,3-dihydroxy-1,4-bis(diphenylphosphino) butane], and (R)-QUINAP [(R)-(+)-1-(2-diphenylphosphino-1-naphthyl) isoquinoline]. The ee's (R) of the hydrosilylation products (CH3CH(OSiR3)Ph) range between - 9 and 53% with the (R)-QUINAP giving the poorest enantioselectivity. The QALE analyses of log( R/S) for (R)-BINAP, (R)-tolyl-BINAP, (R,R)-Me-DUPHOS, and (R,R)-DIOP reveal that the steric effects associated with the silanes are not monotonic.

Studies on the Mechanism of B(C6F5)3-Catalyzed Hydrosilation of Carbonyl Functions

The strong organoborane Lewis acid B(C6F5)3 catalyzes the hydrosilation (using R3SiH) of aromatic and aliphatic carbonyl functions at convenient rates with loadings of 1-4%. For aldehydes and ketones, the product silyl ethers are isolated in 75-96% yield; for esters, the aldehydes produced upon workup of the silyl acetal products can be obtained in 45-70% yield. Extensive mechanistic studies point to an unusual silane activation mechanism rather than one involving borane activation of the carbonyl function. Quantitative kinetic studies show that the least basic substrates are hydrosilated at the fastest rates; furthermore, increased concentrations of substrate have an inhibitory effect on the observed reaction rate. Paradoxically, the most basic substrates are reduced selectively, albeit at a slower rate, in competition experiments. The borane thus must dissociate from the carbonyl to activate the silane via hydride abstraction; the incipient silylium species then coordinates the most basic function, which is selectively reduced by [HB(C6F5)3]-. In addition to the kinetic data, this mechanistic proposal is supported by a kinetic isotope effect of 1.4(5) for the hydrosilation of acetophenone, the observation that B(C6F5)3 catalyzes H/D and H/H scrambling in silanes in the absence of substrate, computational investigations, the synthesis of models for proposed intermediates, and other isotope labeling and crossover experiments.