The search for alternative gold catalyst activators has led us to consider the design of platforms in which a phosphine gold chloride moiety could be activated formation of a pnictogen bond with a neighboring antimony unit. Here, we describe that such a system can be accessed from 4-(diphenylphosphino)-5-(diphenylstibino)-2,7-di--butyl-9,9-dimethylxanthene, by oxidation of the stibine with 3,5-di--butyl--benzoquinone and by coordination of an AuCl unit to the phosphine. This strategy affords a complex in which a Lewis acidic or pnictogen-bond donor catecholatostiborane unit flanks the adjacent gold chloride moiety. This design impacts the catalytic reactivity of the gold center, as reflected by the ability of this complex to catalyze propargyl amide cyclization reactions. Comparisons with a phosphinostiborane ferrocene analog and computations point to the formation of an intramolecular Au-Cl → Sb(V) interaction as responsible for the observed catalytic activity.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1039/d3cc04942f | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Pnictogen Bonding at the Core of a Carbene-Stiborane-Gold Complex: Impact on Structure and Reactivity.
Organometallics
October 2024
Department of Chemistry, Texas A&M University, College Station, Texas 77843-3255, United States.
Our interest in the design of ambiphilic ligands and their coordination to gold has led us to synthesize an indazol-3-ylidene gold chloride complex functionalized at the 4-position of the indazole backbone by a stibine functionality. The antimony center of this new complex cleanly reacts with -chloranil to afford the corresponding stiborane derivative. Structural analysis indicates that the stiborane coordination environment is best described as a distorted square pyramid whose open face is oriented toward the gold center, allowing for the formation of a long donor-acceptor, or pnictogen, Au → Sb bonding interaction.
View Article and Find Full Text PDFPrevalence of contact allergy to gold in dermatitis patients from 2010 to 2024: A systematic review and meta-analysis.
Contact Dermatitis
December 2024
Department of Dermatology and Allergy, National Allergy Research Centre, Herlev and Gentofte Hospital, Herlev, Denmark.
Article Synopsis
- Gold contact allergy is identified through patch testing, but while these tests often show positive results, actual dermatitis cases from everyday gold exposure are uncommon.
- A study aimed to determine the prevalence of gold contact allergy among dermatitis patients by reviewing literature from 2010 to 2024, analyzing 16 studies with nearly 15,000 participants.
- The findings revealed a pooled prevalence of 14.1% for gold contact allergy, indicating variability across studies, and emphasizing the necessity for consistent testing methods and additional research to clarify this allergy's significance.
Curcumin-loaded gold nanoparticles with enhanced antibacterial efficacy and wound healing properties in diabetic rats.
Int J Pharm
December 2024
Department of Pharmaceutics, Faculty of Pharmacy, University of Tabuk, Tabuk 71491, Saudi Arabia. Electronic address:
Article Synopsis
- * This study focuses on improving curcumin's effectiveness by using gold nanoparticles (AuNPs) that enhance its properties, revealing an optimal formulation with small particle size, high drug entrapment efficiency, and better skin absorption.
- * The AuNPs-loaded curcumin demonstrated significantly better wound healing in a diabetic rat model compared to the free drug, with benefits like reduced oxidative stress, increased collagen, and improved antibacterial activity.
Photodynamic and Antibacterial Assessment of Gold Nanoparticles Mediated by Gold (III) Chloride Trihydrate and Sodium Citrate under Alkaline Conditions.
Materials (Basel)
June 2024
Department of Biotechnology, Ming Chuan University, Taoyuan City 33343, Taiwan.
Sodium citrate (SC) is sensitive to violet light illumination (VLI) and acts as a weak reductant. Conversely, gold (III) chloride trihydrate (GC) often acts as an oxidant in a redox reaction. In this study, the influences of colored light on the production of gold nanoparticles (AuNPs) in a mixture of gold (III) ions and citrate via VLI and the antibacterial photodynamic inactivation (aPDI) of () are determined under alkaline conditions.
View Article and Find Full Text PDFElectronic Decoupling and Hole-Doping of Graphene Nanoribbons on Metal Substrates by Chloride Intercalation.
ACS Nano
July 2024
nanotech@surfaces Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf 8600, Switzerland.
Article Synopsis
- Atomically precise graphene nanoribbons (GNRs) exhibit varied electronic properties based on their chemical structure, making them complex to study.
- Various GNRs have been created on metal surfaces, but their interaction with the substrate complicates the understanding of their intrinsic electronic properties.
- The introduction of a dielectric gold chloride layer beneath the GNRs helps to electronically separate them from the metal, allowing for improved investigation of their electronic characteristics, particularly in a hole-doped state.
Want 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!