Taming Radical Pairs in Nanocrystalline Ketones: Photochemical Synthesis of Compounds with Vicinal Stereogenic All-Carbon Quaternary Centers

2018 ◽  
Vol 140 (27) ◽  
pp. 8359-8371 ◽  
Author(s):  
Jordan J. Dotson ◽  
Salvador Perez-Estrada ◽  
Miguel A. Garcia-Garibay
Keyword(s):  
Photochemical Synthesis ◽  
Radical Pairs ◽  
Quaternary Centers

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

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>.

Diverse Cyclopentenes via Enantioselective Cu-Catalyzed Desymmetrization

2018 ◽  
Author(s):  
Reece Jacques ◽  
Robert D. C. Pullin ◽  
Stephen P. Fletcher
Keyword(s):  
Ring Systems ◽  
Quaternary Centers ◽  
Stereogenic Centers

<div> <div> <div> <p>A highly regio-, diastereo- and enantioselective Cu-catalyzed desymmetrization of diverse meso-bisphosphates with alkyl zirconium nucleophiles has been developed. The reaction allows access to a broad range of functionalized cyclopentenes with up to three contiguous stereogenic centers, including quaternary centers and spirocyclic ring systems.</p></div></div></div>

Diverse Cyclopentenes via Enantioselective Cu-Catalyzed Desymmetrization

2018 ◽  
Author(s):  
Reece Jacques ◽  
Robert D. C. Pullin ◽  
Stephen P. Fletcher
Keyword(s):  
Ring Systems ◽  
Quaternary Centers ◽  
Stereogenic Centers

<div> <div> <div> <p>A highly regio-, diastereo- and enantioselective Cu-catalyzed desymmetrization of diverse meso-bisphosphates with alkyl zirconium nucleophiles has been developed. The reaction allows access to a broad range of functionalized cyclopentenes with up to three contiguous stereogenic centers, including quaternary centers and spirocyclic ring systems.</p></div></div></div>

Synthesis of Nitrile-Bearing Quaternary Centers via an Equilibrium-Driven Transnitrilation and Anion-Relay Strategy

2019 ◽  
Author(s):  
Sebastien Alazet ◽  
Michael West ◽  
Purvish Patel ◽  
Sophie Rousseaux
Keyword(s):  
Building Blocks ◽  
One Pot ◽  
Quaternary Centers ◽  
Synthetic Intermediates

The efficient preparation of nitrile-containing building blocks is of interest due to their utility as synthetic intermediates and their prevalence in pharmaceuticals. As a result, significant efforts have been made to develop methods to access these motifs which rely on safer and non-toxic sources of CN. Herein, we report that 2-methyl-2-phenylpropanenitrile is an efficient, non-toxic, electrophilic CN source for the synthesis of nitrile-bearing quaternary centers via a thermodynamic transnitrilation and anion-relay strategy. This one-pot process leads to nitrile products resulting from the gem-difunctionalization of alkyl lithium reagents.<br>

Photochemical Synthesis of Nonplanar Small Molecules with Ultrafast Nonradiative Decay for Highly Efficient Phototheranostics

2021 ◽  
pp. 2102799
Author(s):  
Xiaozhen Li ◽  
Di Zhang ◽  
Guihong Lu ◽  
Tingchao He ◽  
Yingpeng Wan ◽  
...  
Keyword(s):  
Small Molecules ◽  
Photochemical Synthesis ◽  
Nonradiative Decay ◽  
Highly Efficient

scholarly journals Photochemical Synthesis of Gold and Silver Nanoparticles—A Review

Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4585
Author(s):  
Nicole Jara ◽  
Nataly S. Milán ◽  
Ashiqur Rahman ◽  
Lynda Mouheb ◽  
Daria C. Boffito ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Surface Chemistry ◽  
Metallic Nanoparticles ◽  
Colloidal Stability ◽  
Photochemical Synthesis ◽  
Gold And Silver Nanoparticles ◽  
Future Developments ◽  
Technological Advances ◽  
Experimental Parameters ◽  
Sophisticated Equipment

Nanomaterials have supported important technological advances due to their unique properties and their applicability in various fields, such as biomedicine, catalysis, environment, energy, and electronics. This has triggered a tremendous increase in their demand. In turn, materials scientists have sought facile methods to produce nanomaterials of desired features, i.e., morphology, composition, colloidal stability, and surface chemistry, as these determine the targeted application. The advent of photoprocesses has enabled the easy, fast, scalable, and cost- and energy-effective production of metallic nanoparticles of controlled properties without the use of harmful reagents or sophisticated equipment. Herein, we overview the synthesis of gold and silver nanoparticles via photochemical routes. We extensively discuss the effect of varying the experimental parameters, such as the pH, exposure time, and source of irradiation, the use or not of reductants and surfactants, reagents’ nature and concentration, on the outcomes of these noble nanoparticles, namely, their size, shape, and colloidal stability. The hypothetical mechanisms that govern these green processes are discussed whenever available. Finally, we mention their applications and insights for future developments.

Rhodium-catalyzed enone carbonyl directed C–H activation for the synthesis of indanones containing all-carbon quaternary centers

2021 ◽  
Vol 8 (7) ◽  
pp. 1447-1453
Author(s):  
Jiang Lou ◽  
Wenjia Han ◽  
Zhuqing Liu ◽  
Jiaqi Xiao
Keyword(s):  
Diazo Compounds ◽  
Quaternary Centers ◽  
Ketene Dithioacetals

Rhodium(iii)-catalyzed enone carbonyl directed C–H activation/annulation of α-aroyl ketene dithioacetals with diazo compounds has been realized for the synthesis of β-quaternary indanones.

Sign in / Sign up

Export Citation Format

Share Document