A series of nickel(ii) complexes of the type [R-PNP]Ni(ER') ([R-PNP](-) = [N(o-C(6)H(4)PR(2))(2)](-); R = Ph, (i)Pr, Cy; E = NH, O, S; R' = Ph, (t)Bu) featuring unsupported, covalently bound pi-donor ligands have been prepared and characterized. The metathetical reactions of [R-PNP]NiCl (R = Ph, (i)Pr, Cy) with LiNHPh, NaOPh, or NaSPh, respectively, produced the corresponding anilide [R-PNP]Ni(NHPh), phenolate [R-PNP]Ni(OPh), and thiophenolate [R-PNP]Ni(SPh) derivatives. Treatment of [Ph-PNP]NiCl with either LiNH(t)Bu or NaO(t)Bu generated tert-butyl amide [Ph-PNP]Ni(NH(t)Bu) and tert-butoxide [Ph-PNP]Ni(O(t)Bu), respectively. In contrast, attempts to prepare analogous tert-butyl amide and tert-butoxide complexes of [(i)Pr-PNP](-) or [Cy-PNP](-) were not successful. Protonolysis studies of these nickel(ii)-heteroatom complexes revealed the basic reactivity of these pi-donor ligands. The basicity follows the order NH(t)Bu > O(t)Bu > NHPh > OPh > SPh. In addition to solution NMR spectroscopic data for all new compounds, X-ray structures of [(i)Pr-PNP]Ni(NHPh) and [(i)Pr-PNP]Ni(OPh) are presented.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1039/b719894a | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
The Effect of Alkyl Substituents on the Formation and Structure of Homochiral (*,*)-[RGa(-OCH(Me)COR')] Species-Towards the Factors Controlling the Stereoselectivity of Dialkylgallium Alkoxides in the Ring-Opening Polymerization of -Lactide.
Molecules
January 2025
Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland.
Building on our previous studies, which have demonstrated that homochiral propagating species-(*,*)-[MeGa(-OCH(Me)COR)]-were crucial for the heteroselectivity of [MeGa(-OCH(Me)COMe)] in the ring-opening polymerization (ROP) of racemic lactide (-LA), we have investigated the effect of alkyl groups on the structure and catalytic properties of dialkylgallium alkoxides in the ROP of -LA. Therefore, we have isolated and characterized the -[RGa(-OCH(Me)COMe] (R = Et (), Pr () and -[RGa(-OCH(Me)CHN] (R = Et (), Pr ()) complexes, to demonstrate the effect of alkyl groups on the chiral recognition induced the formation of the respective homochiaral species-(*,*)-[RGa(-OCH(Me)COMe)] and (*,*)-[RGa(-OCH(Me)CHN]. Moreover, we have investigated the structure of (,)-[RGa(-OCH(Me)COMe] (R = Et ((,)-, R = Pr ((,)-,) and their catalytic activity in the ROP of -LA.
View Article and Find Full Text PDFIntratumoral and peritumoral radiomics for forecasting microsatellite status in gastric cancer: a multicenter study.
BMC Cancer
January 2025
Department of Radiology, The People's Hospital of PingYang, Wenzhou Medical University, Wenzhou, 325400, China.
Objective: This investigation attempted to examine the effectiveness of CT-derived peritumoral and intratumoral radiomics in forecasting microsatellite instability (MSI) status preoperatively among gastric cancer (GC) patients.
Methods: A retrospective analysis was performed on GC patients from February 2019 to December 2023 across three healthcare institutions. 364 patients (including 41 microsatellite instability-high (MSI-H) and 323 microsatellite instability-low/stable (MSI-L/S)) were stratified into a training set (n = 202), an internal validation set (n = 84), and an external validation set (n = 78).
Prognostic and therapeutic implications of measurable residual disease levels during remission induction of childhood ALL.
Blood
December 2024
St. Jude Children's Research Hospital, Memphis, Tennessee, United States.
We evaluated the prognostic and therapeutic significance of measurable residual disease (MRD) during remission induction in pediatric acute lymphoblastic leukemia (ALL) patients. In the CCCG-ALL-2015 protocol, 7640 patients were categorized into low-, intermediate-, or high-risk groups based on clinical and genetic features. Final risk classification was determined by MRD assessed via flow cytometry on Days 19 and 46 of remission induction, with additional intensified chemotherapy for Day 19 MRD ≥1%.
View Article and Find Full Text PDFRotational Excitation Cross Sections for Chloronium Based on a New 5D Interaction Potential with Molecular Hydrogen.
J Phys Chem A
January 2025
Univ Rennes, CNRS, IPR (Institut de Physique de Rennes)─UMR 6251, F-35000 Rennes, France.
Chloronium (HCl) is an important intermediate of Cl-chemistry in space. The accurate knowledge of its collisional properties allows a better interpretation of the corresponding observations in interstellar clouds and, therefore, a better estimation of its abundance in these environments. While the ro-vibrational spectroscopy of HCl is well-known, the studies of its collisional excitation are rather limited and these are available for the interaction with helium atoms only.
View Article and Find Full Text PDFAnnulated carbocyclic gallylene and bis-gallylene with two-coordinated Ga(i) atoms.
Chem Sci
November 2024
Molecular Inorganic Chemistry and Catalysis, Inorganic and Structural Chemistry, Center for Molecular Materials, Faculty of Chemistry, Universität Bielefeld Universitätsstrasse 25 D-33615 Bielefeld Germany http://www.ghadwalgroup.de.
The first carbocyclic gallylene [(ADC)Ga(GaI)] and bis-gallylene [(ADC)Ga] (ADC = PhC{N(Dipp)C}; Dipp = 2,6-iPrCH) featuring a central CGa ring annulated between two 1,3-imidazole rings are prepared by KC reductions of [(ADC)GaI]. Treatment of [(ADC)Ga] with Fe(CO) affords complex [(ADC)GaFe(CO)] in which each Ga(i) atom serves as a two-electron donor. [(ADC)Ga] activates white phosphorus (P) and the C -F bond of aryl fluorides (ArF) to yield compounds [(ADC)Ga(P)] and -/-[(ADC)GaF(Ar)], respectively.
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!