Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/cr040004c | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Unveiling the Phosphine-Mediated -Transfer from Azide to Isocyanide en Route to Carbodiimides and 4-Imino-1,3,2-diazaphosphetidines.
Org Lett
January 2025
Departamento de Química Orgánica, Facultad de Química, Regional Campus of International Excellence "Campus Mare Nostrum", Universidad de Murcia, E-30100Murcia, Spain.
Intramolecular reactions between isocyano and iminophosphorane functions yield species containing an embedded 1,3,2-diazaphosphetidine ring, as result of the [2 + 2] cycloaddition of the primary reactive product, the cyclic carbodiimide, with a second unit of reactant. DFT studies reveal a first rate-determining step entailing a [2 + 1] cycloaddition involving the isocyanide carbon atom and the P═N double bond, with the further intervention of a dipolar precursor of the intermediate carbodiimide. The 1,3,2-diazaphosphetidine ring of the final products is shown to be hydrolytically and thermally labile.
View Article and Find Full Text PDFConstruction of five- and seven-membered rings facilitated by alkyne-azide functionality: access to quinoline fused triazolo-azepines.
Org Biomol Chem
January 2025
Department of Chemistry, Central University of Punjab, Bathinda, Punjab, 151401, India.
The synthesis of novel quinoline-fused triazolo-azepine derivatives has been reported using an intramolecular 1,3-dipolar azide-alkyne cycloaddition strategy. This method possesses considerable potential to synthesize five- and seven-membered rings in high yields (65-87%) without the necessity of metal catalysts or additives. Additionally, this methodology was applicable to pyridine and tetralone based adducts to afford triazolo-azepine derivatives.
View Article and Find Full Text PDFStudy of PVAc/EVA polymer series: Influence of the inter-/intra-molecular interaction ratio on the molecular mobility at the glass transition.
J Chem Phys
November 2024
Univ. Rouen Normandie, INSA Rouen Normandie, CNRS, Normandie Univ., GPM UMR 6634, F-76000 Rouen, France.
Article Synopsis
- The study focused on the molecular mobility during the glass transition of poly(vinyl acetate) (PVAc) and poly(ethylene-co-vinyl acetate) (EVA) by analyzing how temperature and pressure affect intermolecular interactions.
- Researchers used time-temperature-pressure superpositions and relaxation time dispersion to assess the impact of the vinyl acetate (VAc) ratio on molecular interactions and cooperative behavior.
- Results showed that the thermal and volumetric contributions to isobaric fragility vary based on the VAc ratio and pressure, highlighting the significant role of the dipolar pendant groups in these interactions.
Cyclic Peptide C5aR1 Antagonist Design Using Solution Conformational Analysis Derived from Residual Dipolar Couplings.
ACS Med Chem Lett
November 2024
Medicine Design, Pfizer Inc., 1 Portland Street, Cambridge, Massachusetts 02139, United States.
To gain further insight into the conformational properties of small cyclic peptides that bind to the G-protein coupled receptor C5aR1, we report here for the first time the elucidation of three peptide solution conformations using residual dipolar couplings and NMR temperature coefficients. Each of these peptides varies by at least one amino acid, adopts a different intramolecular hydrogen bonding pattern, and has a different solution conformation. The solution conformations were used in combination with a homology structure of C5aR1 as a design template for increasing the potency of peptide leads for the C5a receptor.
View Article and Find Full Text PDFEnhancement of Single-Molecule Magnet Properties by Manipulating Intramolecular Dipolar Interactions.
Adv Sci (Weinh)
January 2025
Department of Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China.
A new single-molecule magnet (SMM) complex [K(18-crown-6)][(COT)Er(µ-Cl)Er(COT)] (ErCl, COT = cyclooctatetraenide dianion) is obtained by the reaction of [(COT)Er(µ-Cl)(THF)] (ErCl, THF = tetrahydrofuran) with an equivalent of KCl in the presence of 18-crown-6. The two COT-Er units in the newly formed complex are triply bridged by µ-Cl ligands, leading to the "head-to-tail" alignment of the magnetic easy axes distinctly different from the "staggered" arrangement in the precursor complex. This structural transformation has led to significantly enhanced intramolecular dipolar interactions and a reduced transverse component of the crystal fields, increasing the energy barrier from 150(8) K for ErCl to 264(4) K for ErCl and extending its magnetic relaxation time at 2 K by 2500 times with respect to ErCl.
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!