The first frustrated Lewis pair-catalyzed cycloisomerization of a series of 1,5-enynes was developed. The reaction proceeds via the π-activation of the alkyne and subsequent 5-endo-dig cyclization with the adjacent alkene. The presence of PPh3 was of utmost importance on the one hand to prevent side reactions (for example, 1,1-carboboration) and on the other hand for the efficient protodeborylation to achieve the catalytic turnover. The mechanism is explained on the basis of quantum-chemical calculations, which are in full agreement with the experimental observations.
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http://dx.doi.org/10.1002/anie.201511921 | DOI Listing |
Med Humanit
December 2024
Humanities and Social Sciences, National Institute of Technology Tiruchirappalli, Tiruchirappalli, Tamil Nadu, India
This article aims to examine the lived experiences of attention-deficit/hyperactivity disorder (ADHD) diagnosis in adulthood, emphasising its revelatory nature and diverse emotional responses it provokes. The diagnosis serves as a pivotal moment of self-discovery, often evoking feelings of validation and identity affirmation. However, it also triggers a complex array of emotions, including grieving for the childhood self, frustration with society's failure to recognise the legitimate challenges and evolving self-concept post diagnosis.
View Article and Find Full Text PDFJ Am Chem Soc
December 2024
State Key Laboratory of Fluorine & Nitrogen Chemicals, School of Chemical Engineering and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China.
Solid frustrated Lewis pair (FLP) shows remarkable advantages in the activation of small molecules such as CO, owing to the strong orbital interactions between FLP sites and reactant molecules. However, most of the currently constructed FLP sites are randomly distributed and easily reunited on the surface of catalysts, resulting in a low utilization rate of FLP sites. Herein, atomic tungsten-based FLP (N···W FLP) sites are constructed for photocatalytic CO conversion through introducing W single-atoms into polymeric carbon nitride.
View Article and Find Full Text PDFChemphyschem
December 2024
Department of Nanoscience, Joint School of Nanoscience & Nanoengineering (JSNN), University of North Carolina at Greensboro, Greensboro, NC 27401, USA.
To mitigate the adverse effects of CO emissions, CO electroreduction to small organic products is a preferable solution and potential catalysts include the single-atom catalyst (SAC) which comprises individual atoms dispersed on 2D materials. Here, we used aluminum and phosphorus as the active sites for CO electroreductions by embedding them on the 2D graphitic carbon nitride (g-CN) nano-surface. The resulting M-CN (M=Al and P) SACs were computationally studied for the CO electroreduction using density functional theory (DFT) and ab-initio molecular dynamics (AIMD) simulations.
View Article and Find Full Text PDFNat Commun
December 2024
State Key Laboratory for Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, China.
Gas-phase heterogeneous catalytic CO hydrogenation to commodity chemicals and fuels via surface frustrated Lewis pairs is a growing focus of scientific and technological interest. Traditional gas-phase heterogeneous surface frustrated Lewis pair catalysts primarily involve metal oxide-hydroxides (MOH•••M). An avenue to improve the process performance metrics lies in replacing the Lewis base MOH with a stronger alternative; an intriguing example being the amine MNH in metal nitrides.
View Article and Find Full Text PDFSmall Methods
December 2024
Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Jiangsu Province Key Laboratory of Green Biomass-based Fuels and Chemicals, College of Chemical Engineering, Nanjing Forestry University, Nanjing, Jiangsu, 210037, China.
This work reports boron and oxygen dual-doped carbon nitride nanotubes (B/O-CNNTs) prepared via a copolymerization process for electrocatalytic ammonia synthesis from nitrogen gas (NRR) and nitrate (NORR) sources, respectively. By adjusting the dosage of boron oxide precursor, the texture and content of B/O dual dopants and the coordination environment in the resulting 1D CNNTs can be tuned. The best B/O-CNNTs can achieve maximum Faradaic efficiencies of 35% and 96% at -1.
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