In intermolecular Heck reactions of styrene and vinylarenes, the aryl and vinyl groups routinely insert at the β position. However, selective insertion at the α position has been very rare. Herein, we provide a missing piece in the palette of Heck reaction, which gave >20:1 α selectivity. The key to our success is a new ferrocene 1,1'-bisphosphane (dnpf) that carries 1-naphthyl groups. Our mechanistic studies revealed that the high α selectivity is partly attributable to the steric effect of dnpf. The rigid and bulky 1-naphthyl groups of dnpf sterically disfavor β insertion.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/chem.201203646 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Local Structure in Crystalline, Glass and Melt States of a Hybrid Metal Halide Perovskite.
J Am Chem Soc
September 2024
Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States.
The pursuit of structure-property relationships in crystalline metal halide perovskites (MHPs) has yielded an unprecedented combination of advantageous characteristics for wide-ranging optoelectronic applications. While crystalline MHP structures are readily accessible through diffraction-based structure refinements, providing a clear view of associated long-range ordering, the local structures in more recently discovered glassy MHP states remain unexplored. Herein, we utilize a combination of Raman spectroscopy, solid-state nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy, in situ X-ray diffraction (XRD) and pair distribution function (PDF) analysis to investigate the coordination environment in crystalline, glass and melt states of the 2D MHP [(S)-(-)-1-(1-naphthyl)ethylammonium]PbBr.
View Article and Find Full Text PDFCuBr-mediated dehydrogenative [4+2] annulation of 1-naphthyl-1,3-indandiones and alkenes.
Chem Commun (Camb)
August 2024
College of Chemistry and Pharmaceutical Engineering, Nanyang Normal University, Nanyang 473061, China.
Intermolecular annulation reactions of 1-naphthyl-1,3-indandiones with alkenes proceed efficiently in the presence of a copper catalyst to generate spirocarbocycle compounds. Various spirocyclic molecules bearing an all-carbon quaternary center could be obtained by this novel method with good yields, excellent regioselectivity, and good functional group tolerance. A radical mechanism is proposed based on the HRMS analysis results of control experiments.
View Article and Find Full Text PDFThe dimer effect: A refinement approach towards skin sensitization assessment in-chemico using Amino acid Derivative Reactivity Assay.
J Appl Toxicol
November 2024
L'Oréal Research & Innovation, Clichy, France.
Article Synopsis
- * Several non-animal tests have been developed to predict skin sensitizers by examining how chemicals interact with skin proteins, focusing on the initial molecular step where sensitizers form bonds with these proteins.
- * The study introduces a new method to accurately measure the depletion of specific peptides in chemical tests, addressing the problem of overestimating results due to unintended chemical reactions, and demonstrates this method’s effectiveness with three different chemicals.
Redox-Stable and Multicolor Electrochromic Polyamides with Four Triarylamine Cores in the Repeating Unit.
Polymers (Basel)
June 2024
Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei 10608, Taiwan.
Two new triarylamine-based diamine monomers, namely, ,'-bis(4-methoxyphenyl)-,'-bis(4-(4-aminophenyl-4'-methoxyphenylamino)phenyl)--phenylenediamine () and ,'-bis(4-methoxyphenyl)-,'-bis(4-((4-aminophenyl-1-naphthyl)amino)phenyl)--phenylenediamine (), were successfully synthesized and led to two series of electroactive polyamides by polycondensation reactions with common aromatic dicarboxylic acids. The polymers demonstrated multicolored electrochromism, high optical contrast, and remarkable enhancements in redox and electrochromic stability. Compared to other triarylamine-based polymers, the studied polyamides exhibited enhanced electrochromic stability (only 3~6% decay of its coloration efficiency at 445 nm after 14,000 switching cycles) at the first oxidation stage.
View Article and Find Full Text PDFImpact of Alkyl Core Substitution Kinetics in Diaryl Dihydrophenazine Photoredox Catalysts on Properties and Performance in O-ATRP.
ACS Catal
November 2023
Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States.
Organocatalyzed atom transfer radical polymerization (O-ATRP) is a controlled radical polymerization method mediated by organic photoredox catalysts (PCs) for producing polymers with well-defined structures. While -diaryl dihydrophenazine PCs have successfully produced polymers with low dispersity ( < 1.3) in O-ATRP, low initiator efficiencies ( ~ 60-80%) indicate an inability to achieve targeted molecular weights and have been attributed to the addition of radicals to the PC core.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!