1,3-Allyl and 1,2-allyl shifts through [3,3]- and [2,3]-sigmatropic rearrangements are well-established and widely used in organic synthesis. In contrast, 1,5-allyl shift through related [3,5]-sigmatropic rearrangement is unknown because [3,5]-sigmatropic rearrangement is thermally Woodward-Hoffmann forbidden. Herein, we report an unexpected discovery of a formal 1,5-allyl shift of allyl furfuryl alcohol through a 2-step sequential rearrangement. Mechanistically, this formal 1,5-allyl shift is achieved through a sequential ring expansion/contraction rearrangement: 1) Achmatowicz rearrangement (ring expansion), and 2) cascade oxonia-Cope rearrangement/retro-Achmatowicz rearrangement (ring contraction). This new 1,5-allyl shift method is demonstrated with >20 examples and expected to find applications in organic synthesis and materials chemistry.
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http://dx.doi.org/10.1002/anie.202205919 | DOI Listing |
Environ Technol
January 2025
Department of Materials Engineering, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana.
This study synthesises expanded graphite (EG) from graphitised carbon from waste polyethylene terephthalate (PET) bottles. The adsorbent material was characterised using FTIR, XRF, XRD, SEM, Raman Spectroscopy, and BET surface area analysis. The synthesised EG defluorinated wastewater, utilising response surface methodology (RSM) for experimental design and optimisation.
View Article and Find Full Text PDFKnee Surg Sports Traumatol Arthrosc
January 2025
Department of Orthopedic Surgery, Nagoya City University Graduate School of Medical Sciences, Nagoya, Aichi, Japan.
Purpose: Medial meniscus ramp lesions (MMRLs), lateral meniscus posterior root tears (LMPRTs), and anterolateral complex injuries (ALCIs) are major secondary stabiliser injuries associated with anterior cruciate ligament (ACL) injuries. This study aimed to investigate the effect of the number of secondary stabiliser injuries on knee instability in ACL injuries.
Methods: Patients who underwent primary ACL reconstruction between January 2017 and May 2023 were enroled in this study.
Sci Rep
January 2025
Gynecology Department, Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, 210029, China.
The presence of high-risk human papillomavirus (HR-HPV) contributes to the development of cervical lesions and cervical cancer. Recent studies suggest that an imbalance in the cervicovaginal microbiota might be a factor in the persistence of HR-HPV infections. In this study, we collected 156 cervicovaginal fluid (CVF) of women with HR-HPV infection, which were divided into three groups (negative for intraepithelial lesions = 78, low/high-grade squamous intraepithelial lesions = 52/26).
View Article and Find Full Text PDFSci Rep
January 2025
Department of Ophthalmology, Faculty of Medicine, University of Debrecen, Nagyerdei blvd. 98, Debrecen, 4012, Hungary.
This prospective cohort study is aimed to investigate circadian variations in corneal parameters, focusing on sleep-deprived subjects. Sixty-four healthy individuals (age range: 21-76 years) actively participated in this study, undergoing examinations at least five times within a 24-hour timeframe. The analysis encompassed keratometric parameters of the cornea's front (F) and back (B) surfaces, refractive power in flattest and steepest axes (K1, K2), astigmatism (Astig) and its axis (Axis), aspheric coefficient (Asph), corneal pachymetry values of thinnest corneal thickness (Pachy Min) and corneal thickness in the center of the pupil (Pachy Pupil), volume relative to the 3 and 10 mm corneal diagonal (Vol D3, Vol D10) and surface variance index (ISV).
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
January 2025
Department of Geography, Rampurhat College, PO-Rampurhat, Dist-Birbhum, 731224, India.
In fluvial environments, the shifting of river channels and bank erosion are frequently caused by both natural and anthropogenic factors. Riverine hazards like bank erosion and course alterations offer severe issues to the riparian villages along the lower basin of the Tista River in India, which substantially influence the livelihoods of inhabitants living there. This research addressed river channel shifting tendency and identified major bank erosion-prone villages along the lower course of the Tista River and challenges to the livelihoods of the riparian people.
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