: Due to similar reactivity in comparison with aromatic organometallic reagents, diaryliodonium salts are currently in broad usage as less toxic, highly efficient, stable and mild electrophilic reagents in organic synthesis. The hypervalent iodine center of diaryliodonium salts can lead to unique reactivity, which thus is frequently presented in metal-free arylations or metal-involved elementary reactions such as oxidative addition, reduction elimination, ligand coupling and ligand exchange reaction. As such, diaryliodonium salts have experienced explosive growth by transferring aromatics to the target molecules. In contrast to the reviews on the synthetic utility or aryl transformations by using diaryliodonium salts, this review provides a summary of their structures and the synthetic strategies towards them during recent decades.

Palladium-catalyzed C2-arylation/intramolecular acylation with arylcarboxylic acids was developed by using diaryliodonium salts. The protocol has the advantage of good step-economy by two chemical bonds formation in one pot.

Studies on the ecosystem service value (ESV) of gardens are critical for informing evidencebased land management practices based on an understanding of the local ecosystem. By analyzing equivalent value factors (EVFs), this paper evaluated the values of 11 ecosystem services of gardens in the Yellow River Basin of China in 2019. High-precision land use survey data were used to improve the accuracy of the land use classification, garden areas, and spatial distribution of the ESVs of gardens. The results showed that garden ecosystem generally had high ESVs, especially in terms of the ESV of food production, which is worthy of further research and application to the practice of land use planning and management. Specifically, the value of one standard EVF of ecosystem services in 2019 was 3587.04 CNY/(hm 2 •a), and the ESV of food production of gardens was much higher than that of croplands. Garden ecosystem provided an ESV of 1348.66×10 8 CNY/a in the Yellow River Basin. The areas with the most concentrated ESVs of gardens were located in four regions: downstream in the Shandong-Henan zone along the Yellow River, mid-stream in the Shanxi-Shaanxi zone along the Yellow River, the Weihe River Basin, and upstream in the Qinghai-Gansu-Ningxia-Inner Mongolia zone along the Yellow River. The spatial correlation of the ESVs in the basin was significant (global spatial autocorrelation index Moran's I=0.464), which implied that the characteristics of high ESVs adjacent to high ESVs and low ESVs adjacent to low ESVs are prominent. In the Yellow River Basin, the contribution of the ESVs of gardens to the local environment and economy varied across regions. We also put forward some suggestions for promoting the construction of ecological civilization in the Yellow River Basin. The findings of this study provide important contributions to the research of ecosystem service evaluation in the Yellow River Basin.

Iodonium zwitterions are hypervalent iodine compounds in which the iodine center binds to two substituents and carries a positive formal charge which is compensated by a negative charge within the same molecule. Under thermodynamic conditions, iodonium zwitterions allow concerted nucleophilic aromatic substitutions to be performed, followed by rearrangement reactions. In general, nucleophilic aromatic substitutions proceed stepwise, either via an elimination–addition or via an addition–elimination pathway. It has been suggested that nucleophilic aromatic substitutions occur through a transition state which reduces the activation barrier by charge delocalization. The laboratory experiments reported here aim to give students better insight into the concepts of nucleophilic aromatic substitutions and iodonium zwitterions. These experiments can be used to demonstrate a series of important topics and experimental skills in organic chemistry. In addition, they also teach students analytical techniques such as NMR spectroscopy, mass spectrometry, and X-ray diffraction.

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Fractures are the main seepage channels and the critical oil storage space in fracture-vuggy reservoirs. In this paper, the staggered fracture system was abstracted into an orthogonal fracture network. A physical experimental model was made with a laser-etched acrylic plate. The physical experiments of water flooding, gas flooding, water-alternating-gas, and simultaneous-water-and-gas were carried out using the physical experiment model of the fracture network. The results show that gas is more accessible to break through in gas flooding than water in water flooding, resulting in a lower recovery factor. Water-alternating-gas and simultaneous-water-and-gas can effectively improve oil displacement efficiency through the action of gravity difference and the interaction mechanism of gas and water. Increasing the injection rate properly, increasing slug size properly before water and gas breakthrough during water-alternating-gas simultaneous-water-and-gas, and decreasing the gas-water ratio properly during simultaneous-water-and-gas simultaneous-water-and-gas can effectively expand the sweep scope and improve recovery. The experiment provides a basis for efficient water and gas injection development in fracture-vuggy reservoirs.

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For fault-controlled fractured-vuggy reservoirs, the development characteristics of bottom water flooding and water and gas injection flooding under multi-well conditions must be clarified due to the structural complexity. To address this issue, we designed and manufactured fault-controlled physical experimental models based on the geological model of Tarim Oilfield and conducted flooding experiments. The results demonstrate significant variations in bottom water flooding characteristics due to differences in flow capacity within fractures, cavity area in caves, and filled area in caves under different filling modes. Different bottom water rates exhibit varying abilities to overcome gravity and breakthrough capillary resistance, significantly impacting the bottom water flooding characteristics. During the bottom water flooding period, the positioning of production wells primarily affects the macroscopic sweep range, while the filling modes significantly influence the distribution of remaining oil within individual caves. Throughout the three periods of multi-well water and gas injection, the early water injection stage mainly focuses on mobilizing “insufficiently controlled remaining oil” and some “attic remaining oil,” and the middle gas injection stage primarily targets the attic remaining oil. Finally, the late water injection stage aims to lift the oil–gas–water interface and improve oil displacement efficiency. Furthermore, different water and gas flooding directions affect displacement resistance in each channel and the longitudinal sweep range. This paper identifies the direction for the life cycle production of fault-controlled fractured-vuggy reservoirs and presents a mechanistic explanation.