Chromatic Fulleropyrrolidine as Long‐Lived Metal‐Free Catalyst for CO2 Photoreduction Reaction

The formation of shadows behind small particles has been thought to be a geometric process (GP) where the metal cap build up on the particle creates a shadow width the same size as or larger than the particle. This GP cannot explain why gold particle shadow widths are generally larger than the gold particle and may have no appreciable metal cap build up (fig. 1). Ruben and Telford have suggested that particle shadow widths are formed by the width dependent deflection of shadow metal (SM) lateral to and infront of the particle. The trajectory of the deflected SM is determined by the incoming shadow angle (45°). Since there can be up to 1.4 times (at 45°) more SM directly striking the particle than the film surface, a ridge of metal nuclei lateral to and infront of the particle can be formed. This ridge in turn can prevent some SM from directly landing in the metal free shadow area. However, the SM that does land in the shadow area (not blocked by the particle or its ridge) does not stick and apparently surface migrates into the SM film behind the particle.

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Recent advancement in the electrocatalytic synthesis of ammonia

Nanoscale ◽

10.1039/d0nr01359e ◽

2020 ◽

Vol 12 (15) ◽

pp. 8065-8094 ◽

Cited By ~ 6

Author(s):

Xudong Wen ◽

Jingqi Guan

Keyword(s):

Metal Oxide ◽

Oxide Catalysts ◽

Single Atom ◽

Metal Oxide Catalysts ◽

Metal Free ◽

Recent Advancement ◽

Nanocomposite Catalysts

Different kinds of electrocatalysts used in NRR electrocatalysis (including single atom catalysts, metal oxide catalysts, nanocomposite catalysts, and metal free catalysts) are introduced.

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Transition-metal-free catalytic hydroboration reduction of amides to amines

Organic Chemistry Frontiers ◽

10.1039/d0qo01092h ◽

2020 ◽

Vol 7 (21) ◽

pp. 3515-3520

Author(s):

Wubing Yao ◽

Jiali Wang ◽

Aiguo Zhong ◽

Shiliang Wang ◽

Yinlin Shao

Keyword(s):

Transition Metal ◽

Selective Catalytic Reduction ◽

Catalytic Reduction ◽

Value Added ◽

Metal Free

The selective catalytic reduction of amides to value-added amine products is a desirable but challenging transformation.

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Deaminative carbonylative thioesterification of activated alkylamines with thiophenols under transition-metal-free conditions

Organic Chemistry Frontiers ◽

10.1039/d0qo01479f ◽

2021 ◽

Author(s):

Fengqian Zhao ◽

Xiao-Feng Wu

Keyword(s):

Free Radical ◽

Transition Metal ◽

Metal Free

A transition-metal-free radical carbonylation of activated alkylamines with thiophenols has been successfully developed. Various thioesters were selectively produced with moderate to good yields.

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Stereodivergent Alkyne Hydrofluorination Using a Simple Practical Reagent

10.26434/chemrxiv.11962629.v3 ◽

2020 ◽

Author(s):

Rui Guo ◽

Xiaotian Qi ◽

Hengye Xiang ◽

Paul Geaneoates ◽

Ruihan Wang ◽

...

Keyword(s):

Bond Formation ◽

Biologically Active ◽

Dft Studies ◽

Thermodynamic Control ◽

Important Goal ◽

Peptide Bonds ◽

Metal Free ◽

Vinyl Cation ◽

E And Z Isomers ◽

Vinyl Fluorides

Vinyl fluorides play an important role in drug development as they serve as bioisosteres for peptide bonds and are found in a range of biologically active molecules. The discovery of safe, general and practical procedures to prepare vinyl fluorides remains an important goal and challenge for synthetic chemistry. Here we introduce an inexpensive and easily-handled reagent and report simple, scalable, and metal-free protocols for the regioselective and stereodivergent hydrofluorination of alkynes to access both the E and Z isomers of vinyl fluorides. These conditions were suitable for a diverse collection of alkynes, including several highly-functionalized pharmaceutical derivatives. Mechanistic and DFT studies support C–F bond formation through a vinyl cation intermediate, with the (E)- and (Z)-hydrofluorination products forming under kinetic and thermodynamic control, respectively.<br>

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Metal-Free Photoinduced Hydroalkylation Cascade Enabled by an Electron-Donor-Acceptor Complex

10.26434/chemrxiv.11912073 ◽

2020 ◽

Author(s):

José Tiago Menezes Correia ◽

Gustavo Piva da Silva ◽

Camila Menezes Kisukuri ◽

Elias André ◽

Bruno Pires ◽

...

Keyword(s):

Electron Donor ◽

Functional Group ◽

Photoexcited Electron ◽

One Pot ◽

Quaternary Centers ◽

Metal Free ◽

Acceptor Complex ◽

Catalyst Free ◽

Donor Acceptor ◽

Radical Cascade

A metal- and catalyst-free photoinduced radical cascade hydroalkylation of 1,7-enynes has been disclosed. The process is triggered by a SET event involving a photoexcited electron-donor-aceptor complex between NHPI ester and Hantzsch ester, which decomposes to afford a tertiary radical that is readily trapped by the enyne. <a>The method provides an operationally simple, robust and step-economical approach to the construction of diversely functionalized dihydroquinolinones bearing quaternary-centers. A sequential one-pot hydroalkylation-isomerization approach is also allowed giving access to a family of quinolinones. A wide substrate scope and high functional group tolerance was observed in both approaches</a>.

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