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A selenium‐catalyzed electrophilic cascade reaction of vinylarenes with N‐fluorobenzenesulfonimide for the efficient synthesis of important β‐keto sulfones via a single operation is developed. The reactions of vinylarenes bearing electron‐withdrawing groups and electron‐donating groups proceeded smoothly in the air and gave products in up to 94 % yield. Mechanistic studies suggest that vinyl amines generated by oxidative amination of vinylarenes are the intermediates, the cleavage of N−S bond and the recombination of sulfonyl radical lead to 1,3‐migration of sulfonyl, and hydrolysis affords the products β‐keto sulfones. [ABSTRACT FROM AUTHOR]

Water is essential to human survival; however, many people, particularly those in poorer countries, lack access to reliable sources of clean and safe water. Despite decades of effort to address this issue, water sustainability remains elusive even today. Smart technologies have been widely adopted for water management, rendering smart water management a promising path to achieving water sustainability. Nevertheless, the efficacy of such smart water management in attaining sustainability remains unclear. This study aims to investigate the progress made in pursuing water sustainability with smart water management through a scientometric literature review. The Scopus database was employed to extract a pool of 460 candidate publications, which were then analyzed for content using bibliometric analysis and VOSviewer software. Nine clustered research themes were classified, corresponding to the nine targets of sustainable development goals (SDGs) for water. The findings show that engagement across these topics is highly unequal, providing substantial guidance on where emerging research efforts should be concentrated. The novelty of this study mainly lies in the SDG perspective that provides a significant but overlooked angle for observing progress in smart water management domain. The findings can enlighten the international water industry to create a more favorable environment for regions lagging in using smart technologies to facilitate overall water sustainability. [ABSTRACT FROM AUTHOR]

In China, public–private partnership (PPP) projects consist of six phases, from inception to completion. In the final phase, known as the transfer phase (TP), the project assets are transferred back to the government, and the project is effectively closed out. Although success factors (SF) covering the earlier phases of PPPs have been well-documented, little is known about the effective execution of the TP in China. The main reason is that PPPs are a relatively new phenomenon, with few having reached the end of their life cycle, although this is happening now. Consequently, the determination of critical success factors (CSFs) in the TP is of great interest. This study aims to identify those CSFs that are most impactful to the success of the TP. A total of 23 process factors, arranged in four factor groups, are taken from an earlier study. These factors were presented to China's water PPP project experts in an online questionnaire, with 52 valid responses returned. Of the 23 process factors, 22 were revealed to be statistically critical to the success of the TP, which were identified as critical transfer success factors (CTSFs). The top five CTSFs are (1) contract system, (2) infrastructure, (3) transferred assets, (4) transfer acceptance criteria, and (5) overhaul information. The identification of the relative criticality of CTSFs and, in particular, the identification of the leading factors, can be expected to support the government and contractor entities in effecting the smooth transfer of many Chinese PPP water projects approaching maturity. [ABSTRACT FROM AUTHOR]

Public–private partnership (PPP) infrastructure projects progress through separate phases, with each phase subject to unique risks, thereby requiring a phase-based strategy for managing risks. To date, most research on PPP risk has emphasized phases, with an obvious neglect of the final, transfer phase (TP) of PPP projects, in which the project ownership reverts to government. This study identified and evaluated critical risk categories of the TP, using China's PPP water sector as the context of analysis. A two-stage approach was adopted, including both qualitative and quantitative research methods. Seven critical transfer risk categories (CTRCs) were identified, namely overhaul risks, contract risks, posttransfer operation risks, residual value risks, political risks, information risks, and succeeding operator risks, of which three are unique to the TP. Expert recommendations were presented for the facilitation of a smooth transfer of water PPPs in China. The findings of this study contribute to the body of knowledge in PPP risk management, and the specialized research approach employed may be utilized in similar exploratory studies. [ABSTRACT FROM AUTHOR]

FeCl3‐catalyzed diastereospecific synthesis of tetrahydrobenzo[a]acridin‐5(6H)‐ones from enaminones was described. Single diastereoisomers were obtained in good to excellent yields. Two C−C bonds and three contiguous stereogenic centers were formed. [ABSTRACT FROM AUTHOR]

A novel and efficient catalyst system was developed for homocoupling reactions of aryl halides. The catalyst system consists of Pd(OAc)2 and the peppery sensory component of tobacco leaves. This is the first time that a sensory component has been used in an organic reaction. Experiments using the catalyst system showed that the reactions proceeded smoothly under air in the absence of both an additional ligand and a reductant. Furthermore, the catalyst system can be applied to the coupling reactions of hetaryl iodides. Many functional groups (including a hydroxy group) are tolerated. [ABSTRACT FROM AUTHOR]

Micronized CaO with pores was synthesized by calcining the reaction product CaCO3 from NH4HCO3 and Ca(OH)2. Scanning electron microscopy, X‐ray diffraction, energy dispersive X‐ray spectroscopy, X‐ray fluorescence, Fourier transform infrared spectroscopy, and Brunauer–Emmett–Teller analysis were used to characterize CaO, which confirmed that after calcining at 800°C for 2 hr, CaCO3 was completely converted into porous micronized CaO with a surface area of about 7.295 m2/g and a particle size of 0.5–1.5 μm. The porous CaO microparticles were used as heterogeneous catalysts for producing biodiesel from transesterification of soybean oil and methanol. The influences of reaction time, calcined temperature, and reusability of CaO were explored. The experiments showed that CaO has high catalytic activity for transesterification reaction, and the yield of biodiesel reaches more than 98% under the conditions of methanol/oil mole ratio of 9, and the catalyst amount (catalyst/oil) of 3% after reaction for 2.5 hr. The CaO catalyst can be recycled easily and it also has the advantage of low pollution. Simple synthetic route, low cost, high catalytic activity, good reusability, and great potential for industrialization are the advantages of the porous micronized CaO catalyst that was proposed in this work. [ABSTRACT FROM AUTHOR]

Direct conversion of cheap methylarenes to benzylic amines, which are essential structural units of important drugs, is of great significance. However, the known methodologies suffer from the requirement of noble metal catalysts, heavy metal residues or strong oxidants. Herein, the first biocompatible iron-catalyzed benzylic C (sp 3 )-H amination of methylarenes with N -fluorobenzenesulfonimide is described. The reactions of methylarenes bearing electron-donating groups and electron-withdrawing groups ran smoothly under ligand and additional oxidant free conditions. Both toluene derivatives and 8-methylquinoline can be aminated by the same iron catalyst., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

The combination of zirconocene-mediated coupling of silylated alkynes with a protonation-desilylation or bromination-desilylation process afforded otherwise unavailable butadiene derivatives. When (E,E)-2,3-dialkyl-1,4-bis(trimethylsilyl)-1,3-butadienes were treated with 3 equiv of Br(2) in CH(2)Cl(2), (E)-2,3-dialkyl-1,1,4,4-tetrabromo-2-butenes were obtained in excellent yields with perfect stereoselectivity.

[reaction: see text] The titanium catalyst, which was generated in situ from titanocene dichloride and 2 equiv of butyllithium, was found to catalyze hydrosilation of a variety of alkynes with excellent regio- and syn-selectivity.