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Due to its unique physical and electrophilic properties, the difluoromethyl group (−CF2H) has been playing an irreplaceable role in the field of pharmaceutical and agrochemical industry. Methods that could efficiently incorporate the difluoromethyl group into the target molecules are increasing in the recent years. Developing a stable and efficient difluoromethylating reagent is thus highly attractive. In this review, we describe the development of a nucleophilic difluoromethylation reagent [(SIPr)Ag(CF2H)], including its elemental reaction, difluoromethylation reaction with different types of electrophiles, and its application in the synthesis of a nucleophilic and an electrophilic difluoromethylthiolating reagent. [ABSTRACT FROM AUTHOR]

The quest of the active species in copper‐mediated difluoromethylation of aryl halides led to the discovery of a powerful difluoromethylating reagent [Ph4P]+[Cu(CF2H)2]−2. Complex 2 was able to difluoromethylate a variety of electrophiles including electron‐deficient and electron‐rich aryl iodides, heteroaryl iodides, activated heteroaryl bromides, chloride and aryl bromides with a directing group, as well as other electrophiles such as alkenyl iodide, benzyl bromides, allyl bromides, alkyl iodide, allyl carbonates and acid chloride. In addition, in the presence of an oxidant, complex 2 reacted with various lithium nbutyl arylboronic acid pinacol esters, alkyne and heteroarene. Moreover, complex 2 could transmetalate the difluoromethyl reagent to other metals such as [Ph4P]+[CuCl2]− and [(DPPF)PdCl2]. [ABSTRACT FROM AUTHOR]

China's Grain for Green Program (GGP) is the largest reforestation program in the world. Previous studies lacked targeted assessments regarding its effectiveness in vegetation conversion. Using the time series of Vegetation Continuous Fields in southwest China, we derived the spatiotemporal variations in total vegetation cover, short vegetation (SV) cover and tree canopy (TC) cover during the period from 2000 to 2016. By conducting residual trend analyses independently on the SV and TC cover time series, the trends in human‐induced SV cover (SVH) and TC cover (TCH) were detected. Then, we performed overlay analyses to derive the human‐induced SV–TC conversion in cropland. The study found that the SV in southwest China showed a net browning trend whereas the TC presented a net greening trend. Approximately 69.5% of the pixels with a significant browning trend in SVH showed a significant greening trend in TCH. Furthermore, 50.6% of the human‐induced SV–TC conversion in southwest China occurred in cropland, and the proportion was even larger for the eastern provinces. Our study provides a targeted evaluation of the performance of the GGP and highlights that the implementation of the GGP has caused widespread SV–TC conversion that potentially mitigates global climate change. [ABSTRACT FROM AUTHOR]

The quest of the active species in copper-mediated difluoromethylation of aryl halides led to the discovery of a powerful difluoromethylating reagent [Ph 4 P] + [Cu(CF 2 H) 2 ] - 2. Complex 2 was able to difluoromethylate a variety of electrophiles including electron-deficient and electron-rich aryl iodides, heteroaryl iodides, activated heteroaryl bromides, chloride and aryl bromides with a directing group, as well as other electrophiles such as alkenyl iodide, benzyl bromides, allyl bromides, alkyl iodide, allyl carbonates and acid chloride. In addition, in the presence of an oxidant, complex 2 reacted with various lithium nbutyl arylboronic acid pinacol esters, alkyne and heteroarene. Moreover, complex 2 could transmetalate the difluoromethyl reagent to other metals such as [Ph 4 P] + [CuCl 2 ] - and [(DPPF)PdCl 2 ]., (© 2022 Wiley-VCH GmbH.)

A process for the concurrent transfer of both the NHC ligand and the difluoromethyl group from [(SIPr)Ag(CF 2 H)] to PdX 2 (X = Cl, OAc, and OPiv) for the preparation of [(SIPr)Pd(CF 2 H)X] complexes is described. These complexes were air-stable and easily underwent transmetalation with aryl pinacol boronate/reductive elimination to generate ArCF 2 H in high yields. Based on this discovery, the first one-pot C-H borylation and difluoromethylation process for the preparation of difluoromethylated (hetero)arenes was developed.

Objective: To establish SMMC-7721 human hepatocellular carcinoma cell line stably expressing hepatitis C virus (HCV) core protein., Methods: A lentiviral vector containing HCV core gene was constructed and transfected into HEK293T cells to package recombinant lentivirus (rLV-core) containing ZsGreen and HCV core genes. The SMMC-7721 cells were infected with the rLV-core. The expression of HCV core mRNA was examined by real-time fluorescent quantitative PCR and the HCV core protein was detected by immunofluorescence cytochemistry and Western blotting. The stably transfected cell line was screened., Results: The lentiviral vector was confirmed by enzyme digestion and sequencing. The green fluorescence was seen under fluorescence microscope 48 hours after virus packaging. The SMMC-7721 cell line stably expressing HCV core protein was obtained after infected with the rLV-core. Real-time PCR showed the expression of HCV core mRNA, and both immunofluorescence cytochemistry and Western blotting verified the expression of HCV core protein., Conclusion: The SMMC-7721 human hepatocellular carcinoma cell line stably expressing HCV core protein has been established successfully.