ChemInform Abstract: Synthesis of Spiro[chroman/tetrahydrothiophene-3,3′-oxindole] Scaffolds via Heteroatom-Michael-Michael Reactions: Easily Controlled Enantioselectivity via Bifunctional Catalysts.

By varying the steric and electronic surroundings of the hydrogen-bonding motif, the novel chiral Cinchona-alkaloid based selenoureas were developed. Acting as bifunctional catalysts, they were applied in the Michael reactions of dithiomalonate and nitrostyrene providing chiral adducts with up to 96% ee. The asymmetric Michael–-hemiacetalization reaction of benzylidene pyruvate and dimedone, performed with the assistance of 5 mol% of selenoureas, furnished the product with up to 93% ee and excellent yields. The effectiveness of the new hydrogen-bond donors was also proved in solvent-free reactions under ball mill conditions, supporting the sustainability of the devised catalytic protocol.

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Enantioselective Michael Addition of Malonates to Enones

Current Organic Chemistry ◽

10.2174/1385272824666200316122221 ◽

2020 ◽

Vol 24 (7) ◽

pp. 746-773

Author(s):

Péter Bakó ◽

Tamás Nemcsok ◽

Zsolt Rapi ◽

György Keglevich

Keyword(s):

Michael Addition ◽

Activity Relationship ◽

Chalcone Derivatives ◽

Michael Additions ◽

Michael Reactions ◽

Structure Activity ◽

Cyclic Enones ◽

Michael Acceptors ◽

Relationship Of ◽

Enantioselective Catalysts

: Many catalysts were tested in asymmetric Michael additions in order to synthesize enantioenriched products. One of the most common reaction types among the Michael reactions is the conjugated addition of malonates to enones making it possible to investigate the structure–activity relationship of the catalysts. The most commonly used Michael acceptors are chalcone, substituted chalcones, chalcone derivatives, cyclic enones, while typical donors may be dimethyl, diethyl, dipropyl, diisopropyl, dibutyl, di-tert-butyl and dibenzyl malonates. This review summarizes the most important enantioselective catalysts applied in these types of reactions.

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Conversion of Methanol on Rutile TiO2 (110) and Tungsten Oxide Clusters: 1. Population of Defect-Dependent Thermal Reaction Pathways

Physical Chemistry Chemical Physics ◽

10.1039/d1cp01175h ◽

2021 ◽

Author(s):

Lars Mohrhusen ◽

Katharina Al-Shamery

Keyword(s):

Tungsten Oxide ◽

Single Crystals ◽

Model System ◽

Thermal Reaction ◽

Reaction Pathways ◽

Bifunctional Catalysts ◽

Rutile Tio2 ◽

Reaction Routes ◽

And Tungsten

Tungsten oxide clusters deposited on rutile TiO2 (110) single crystals were used as a model system for heterogenous oxide-oxide bifunctional catalysts. The population of different thermal reaction routes in methanol...

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Hydrotreatment of FCC Gasoline Catalyzed by CoMo Bifunctional Catalysts: The Effects of Acidity on Catalytic Performance

Industrial & Engineering Chemistry Research ◽

10.1021/acs.iecr.0c04437 ◽

2020 ◽

Author(s):

Jingye Chen ◽

Butian Xia ◽

Meng Zheng ◽

Yuhao Zhang ◽

Liyuan Cao ◽

...

Keyword(s):

Catalytic Performance ◽

Bifunctional Catalysts ◽

Fcc Gasoline

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Construction of hierarchical IrTe nanotubes with assembled nanosheets for overall water splitting electrocatalysis

Journal of Materials Chemistry A ◽

10.1039/d1ta01839f ◽

2021 ◽

Author(s):

Ziqiang Wang ◽

Peng Wang ◽

Hugang Zhang ◽

Wenjing Tian ◽

You Xu ◽

...

Keyword(s):

Water Splitting ◽

Oxygen Evolution ◽

Bifunctional Catalysts ◽

Overall Water Splitting ◽

Electrochemical Water Splitting

The design of efficient bifunctional catalysts for hydrogen and oxygen evolution reactions is significant for electrochemical water splitting. Here, hierarchical IrTe nanotubes (NTs) with assembled nanosheets have been prepared through...

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