57956-47-5

Upstream product

• 42201-84-3 1-ethoxy-1-(tert-butyldimethylsilyloxy)ethene 
• 100-52-7 benzaldehyde 
• 69739-34-0 t-butyldimethylsiyl triflate 
• 94-02-0 ethyl 3-oxo-3-phenylpropionate 
• 18162-48-6 tert-butyldimethylsilyl chloride 

Downstream Products

• 5764-85-2 Ethyl 3-hydroxy-3-phenylpropanoate 
• 31796-72-2 phenyl(2-pyridinyl)methanol 
• 329353-55-1 1-[2-(tert-butyl-dimethyl-silanyloxy)-2-phenyl-ethyl]-2-ethyl-cyclopropanol 
• 129679-71-6 3-(tert-butyldimethylsilyloxy)-3-phenylpropanaldehyde 

Relevant academic research and scientific papers

Photocatalytic Vicinal Aminopyridylation of Methyl Ketones by a Double Umpolung Strategy

A photocatalytic double umpolung strategy for the vicinal aminopyridylation of ketones was developed using pyridinium N?N ylides. The inversion of the polarity of the pyridinium N?N ylides by single-electron oxidation successfully enables radical-mediated 1,3-dipolar cycloadditions with enolsilanes formed in situ from ketones, followed by homolytic cleavage of the N?N bond. Intriguingly, the nucleophilic amino and electrophilic pyridyl groups in the ylides can be installed at the nucleophilic α-position and electrophilic carbonyl carbon, respectively, which are typically inaccessible by their innate polarity-driven reactivity. This method accommodates a broad scope, and the utility was further demonstrated by the late-stage functionalization of complex biorelevant molecules. Moreover, the strategy can be successfully applied to enamides.

Chiral Modification of the Tetrakis(pentafluorophenyl)borate Anion with Myrtanyl Groups

The synthesis and characterization of chiral [B(C6F5)4]– derivatives bearing a myrtanyl group instead of a fluoro substituent in the para position are described. These new chiral borates were isolated as their bench-stable lithium, sodium, and cesium salts. The corresponding trityl salts were prepared and tested as catalysts in representative counteranion-directed Diels–Alder reactions and Mukaiyama aldol additions but no enantioselectivity was obtained. Preformation of a chalcone-derived silylcarboxonium ion with the chiral borate as counteranion did not lead to any asymmetric induction in a reaction with cyclohexa-1,3-diene.

Synthesis of a Chiral Borate Counteranion, Its Trityl Salt, and Application Thereof in Lewis-Acid Catalysis

The preparation of a chiral derivative of [B(C6F5)4]– in which the fluorine atom in the para position of each of the C6F5 groups is replaced by a 1,1′-binaphthalen-2-yl group is described. The new counteranion was isolated as its lithium, sodium, and trityl salts. The chiral trityl salt was then used as a catalyst in selected counteranion-directed Diels–Alder reactions and a Mukaiyama aldol addition, but no asymmetric induction was achieved. Application of the chiral trityl salt to the generation of silicon cations by silicon-to-carbon hydride transfer from hydrosilanes failed, presumably as a result of the incompatibility of the relatively electron-rich naphthyl groups in the borate and the cationic silicon electrophiles.

Cooperative organocatalysis of Mukaiyama-type aldol reactions by thioureas and nitro compounds

A unique organocatalytic system for Mukaiyama-type aldol reactions based on the cooperative action of nitro compounds and thioureas has been identified. This system is compatible with a wide range of substrates and does not require low temperatures, inert atmospheres, or an aqueous workup. A catalytic mechanism based on nitro group-mediated silyl cation transfer has been proposed.

The Mukaiyama aldol and Mukaiyama-Michael reactions promoted by commercially available molecular sieves

The Mukaiyama aldol reaction of silyl ketene acetals with aldehydes has been effected by using commercially available 4 molecular sieves (4 MS) as a promoter. Various silyl ketene acetals and silyl enol ethers have been shown to be effective nucleophiles

Organotin perchlorates as gentle Lewis acid catalysts in Mukaiyama reaction

Organotin perchlorates catalyze Mukaiyama reaction of ketene silyl acetal in highly chemoselective but uncommon manners. The competition reaction between aldehyde and acetal leads to exclusive formation of the aldehyde aldols leaving the acetal counterpar

Reversal of Chemoselectivity in Organotin Lewis Acid-Catalyzed Reaction of Ketene Silyl Acetal with Aldehyde and α-Enal

The organotin Lewis acid-catalyzed reaction of ketene silyl acetal with aldehydes results in reversal of chemoselectivity: α-enals react preferentially or exclusively in competition with an alkanal or even aromatic aldehydes.

Metal versus silyl triflate catalysis in the Mukaiyama aldol addition reaction

A mechanistic study of the Mukaiyama aldol addition reaction employing benzaldehyde and hydrocinnamaldehyde along with a selection of Lewis acids including BF3 · OEt2, LiClO4, Yb(OTf)3, Sn(OTf)2, and Zn(OTf)2 is presented. The results of experiments conducted with doubly-labeled silyl ketene acetals implicate a Lewis acidic silicon species and not the metals as the catalyst in the Mukaiyama aldol addition reaction.

Reversal Phenomena of the Preferential Activation of Aldehydes to the Corresponding Acetals under Non-Basic Conditions. The Chemoselective Aldol Reaction of Aldehydes with t-Butyldimethylsilyl Enol Ethers Using TBSCl-InCl3 as a Catalyst

In the presence of a catalytic amount of t-butyldimethylsilyl chloride (TBSCl) and indium(III) chloride (InCl3), aldehydes smoothly react with t-butyldimethylsilyl enol ethers to afford the corresponding aldol adducts in good yields whereas acetals do not

Catalytic Asymmetric Aldol Reaction of Ketene Silyl Acetals with Aldehydes by Use of Chiral Bissulfonamido Zinc(II)

Enantioselective aldol reaction of ketene silyl acetals with aldehydes is effectively performed by use of a catalytic amount of chiral bissulfonamido zinc(II), easily prepared from diethylzinc and chiral sulfonamides.