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A new copper‐catalyzed sp3‐carbon radical/halogen radical cross‐coupling strategy for the formation of C(sp3)‐X bond is described. This provides a general method for synthesis of α‐halogenated and α,α‐dihalogenated‐1,3‐dicarbonyl compounds using sodium halides as halogen source under mild conditions. [ABSTRACT FROM AUTHOR]

JPZ acknowledges financial support from the National Natural Science Foundation of China (No. 21172163, 21472133), the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD), and Key Laboratory of Organic Synthesis of Jiangsu Province (KJS1749). [ABSTRACT FROM AUTHOR]

In the present work, graphene oxide nanoribbons (GONRs) were synthesized via the longitudinal unzipping of multi-walled carbon nanotubes (MWCNTs) nanoparticles with the aid of strong oxidants. The MnO 2 /reduced graphene oxide Nanoribbons (MnO 2 /rGONRs) composites were successfully fabricated by means of a reproducible and single-step hydrothermal co-reduction of KMnO 4 and GONRs. The morphology and composition of as-prepared materials were studied by scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy and X-ray diffraction (XRD). The as-prepared MnO 2 /rGONRs were employed in fabricating a nonenzymatic electrochemical sensor for the sensitive detection of hydrogen peroxide (H 2 O 2 ). The electrochemical properties of the MnO 2 /rGONRs modified glassy carbon electrode (MnO 2 /rGONRs/GCE) were studied by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The developed nonenzymatic electrochemical sensor exhibited well-defined amperometric response towards H 2 O 2 in a wide linear range of 0.25–2245 μM, and a detection limit of 0.071 μM (S/N = 3) could be obtained. And the proposed sensor also displayed excellent electrochemical analytical performance, acceptable reproducibility, high accuracy, and great anti-interference ability. The proposed sensor was applied for the determination of H 2 O 2 in real sample of fetal bovine serum (FBS), and acceptable accuracy and recovery could be obtained. [ABSTRACT FROM AUTHOR]

Steric hindrance due to bulky groups adjacent to the position of attack by the trifluoromethyl radical decreases the yields. [ABSTRACT FROM AUTHOR]

Background: The diagnosis of small bowel diseases is challenging and device assisted enteroscopy (DAE) is a technique for visualizing the entire small bowel. DAE is considered as a safe procedure and the reported rate of adverse events associated with DAE in the literature is low., Objective: The present study tried to investigate the actual incidence of AP after DAE with a systematic review and meta-analysis of available relevant studies., Methods: Studies were searched through the PubMed, EMBASE, and Cochrane library databases. The following data were extracted from all eligible studies: author, country, publication year, publication type, study design, type of DAE used, route of DAE, number of patients with AP after DAE, and number of patients with hyperamylasemia after DAE.A random-effects model with RStudio version 4.2.0 was performed in all analyses. Heterogeneity was assessed using the I 2 test. The risk of bias was assessed by the Newcastle-Ottawa Scale criteria and the publication bias was assessed by the Egger test., Results: Twenty three studies involving a total of 11145 patients were included in the analysis. The overall, pooled AP rate after DAE was 1% (95% CI:0-1%). There was significant heterogeneity among the studies (I 2 = 65%; P < 0.01).The pooled AP rate was 1% (95% CI:0-2 %)in peroral route group. The pooled proportion of patients having hyperamylasemia after DAE was 29% (95% CI: 16-46%).Among the patients who had hyperamylasemia AP were identified in 2% (95% CI: 0-6%) of patients., Conclusion: The incidence of AP after DAE is about 1%. Hyperamylasemia is a common change in the patients undergoing DAE and only 2% of the patients with hyperamylasemia present with AP., Competing Interests: The authors declare that research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Xiao-Dong Shao MD, Hao-Tian Shao MD, Le Wang MD, Yong-Guo Zhang MD, Ye Tian MD, Cheng-Kun Li MD.)

A Cu I -catalyzed cross-coupling of alkyl- and phosphorus-centered radicals for C(sp 3 )-P bond formation is introduced. Diacyl peroxides, generated in situ from aliphatic acids and H 2 O 2 , serve as a source for alkyl radicals and also an initiator for the generation of phosphorus radicals from H-P(O) compounds.

A copper-catalyzed radical C sp 3 -H/P(OR) 3 cross-coupling reaction for the formation of C sp 3 -P bonds is described. A range of 1,3-dicarbonyl compounds and trialkylphosphites were coupled in this fashion to give the corresponding products in moderate to good yields. This protocol provides direct access to α-phosphonyl 1,3-dicarbonyl compounds.