The electronic spectra of 2-bromoethylbenzene and its chloro and fluoro analogues have been recorded by resonant two-photon ionisation (R2PI) spectroscopy. Anti and gauche conformers have been assigned by rotational band contour analysis and IR-UV ion depletion spectroscopy in the CH region. Hydrate clusters of the anti conformers have also been observed, allowing the role of halocarbons as hydrogen bond acceptors to be examined in this context. The donor OH stretch of water bound to chlorine is red-shifted by 36 cm, or 39 cm in the case of bromine. Although classed as weak H-bond acceptors, halocarbons are favourable acceptor sites compared to π systems. Fluorine stands out as the weakest H-bond acceptor amongst the halogens. Chlorine and bromine are also weak H-bond acceptors, but allow for more geometric lability, facilitating complimentary secondary interactions within the host molecule. Ab initio and DFT quantum chemical calculations, both harmonic and anharmonic, aid the structural assignments and analysis.
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http://dx.doi.org/10.1039/c7cp07365h | DOI Listing |
Environ Sci Technol
January 2025
State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
Despite advancements in high-resolution screening techniques, the identification of novel perfluoroalkyl and polyfluoroalkyl substances (PFAS) remains challenging without prior structural information. In view of this, we proposed and implemented a new data-driven algorithm to calculate spectral similarity among PFAS, facilitating the generation of molecular networks to screen for unknown compounds. Using this approach, 81 PFAS across 12 distinct classes were identified in soil samples collected near an industrial park in Shandong Province, China, including the first reported occurrence of 12 iodine-substituted PFAS.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, P. R. China.
Hexafluoropropylene oxide trimer acid (HFPO-TA, CF(CFOCF(CF))COOH) is widely used as an alternative to perfluorooctanoic acid (PFOA), but whether it is a safe alternative requires further evaluation. In this study, male mice were exposed to three dosages (0.56, 2.
View Article and Find Full Text PDFChemosphere
February 2025
Water Resources Research Institute of Shandong Province, Ji'nan, 250013, China. Electronic address:
Both perfluorooctanoic acid (PFOA) and polystyrene microplastics (PS-MPs) are emerging contaminants commonly found in aqueous environments. In co-contaminated areas, MPs may act as carriers for PFOA, complicating transport dynamics. However, information on their cotransport in porous media is limited.
View Article and Find Full Text PDFJ Chromatogr A
January 2025
Key Laboratory of Rare Earths, Ganjiang Innovation Academy, Chinese Academy of Sciences, Ganzhou 341000, China. Electronic address:
A homogeneous liquid-liquid microextraction technique based on switchable deep eutectic solvent (SDES-HLLME), combined with gas chromatography-triple quadrupole tandem mass spectrometry (GC-MS/MS), was developed for the extraction and analysis of 16 polychlorinated biphenyls (PCBs) in water samples. CO-responsive switchable deep eutectic solvent (SDES), which consists of monoethanolamine (MEA) being used as a hydrogen bond acceptor (HBA) and 3-methoxyphenol (3-MP) being used as a hydrogen bond donor (HBD), was used as the extractant, thus providing an environmentally friendly alternative to conventional toxic organic solvents. The study systematically investigated the effects of various parameters on extraction efficiency, including the type and volume of SDES, vortexing duration, CO bubbling time, centrifugation rate and time, ionic strength.
View Article and Find Full Text PDFAAPS PharmSciTech
December 2024
Centre for Pharmaceutical Nanotechnology, Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67 S.A.S., Nagar, Punjab, 160062, India.
Triple negative breast cancer (TNBC) exhibits higher susceptibility towards oxaliplatin (OXA) due to a faulty DNA damage repair system. However, the unfavorable physicochemical properties and risk of toxicities limit the clinical utility of OXA. Therefore, to impart kinetic inertness, site-specific delivery, and multidrug action, an octahedral Pt(IV) prodrug was developed by using chlorambucil (CBL) as a choice of ligand.
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