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Here we report a mild protocol for benzylic C−H trifluoromethylthiolation using sodium decatungstate (NaDT) as the photocatalyst. Wherein, photoactivated DT abstracted the benzylic hydrogen atom via a radical process. This transformation works well with a slight excess of benzylic substrates or as limiting reagents for better purification. The reaction shows mild conditions and good functional group tolerance. Moreover, the protocol could be applied to gram‐scale synthesis. [ABSTRACT FROM AUTHOR]

In this study, we present an efficient and straightforward dearomative hydroalkylation of indoles. By utilizing alkanes or ethers as alkyl radical sources and employing TBADT as a cost‐effective photocatalyst for direct hydrogen atom transfers (HAT), we achieved successful conversion of these heterocyclic derivatives into 2‐alkylindolines with good to excellent yields and high diastereoselectivity under mild reaction conditions. [ABSTRACT FROM AUTHOR]

Herein we describe a sustainable and efficient photocatalytic method for the stereoselective radical alkylation of chiral sulfinyl imines. By employing readily available non‐prefunctionalized radical precursors and the cost‐effective TBADT as a direct HAT photocatalyst, we successfully obtain diverse chiral amines with high yields and excellent diastereoselectivity under mild conditions. This method provides an efficient approach for accessing a diverse array of medicinally relevant compounds, including both natural and synthetic α‐amino acids, aryl ethyl amines, and other structural motifs commonly found in approved pharmaceuticals and natural product. [ABSTRACT FROM AUTHOR]

We developed a site‐selective intermolecular C(sp3)−H alkylation of saccharides with electron‐deficient alkenes using photocatalysis by anthraquinone and tetrabutylammonium decatungstate (TBADT). The main reaction site of anthraquinone‐catalyzed C(sp3)−H alkylation is determined by the weakness of the C−H bond. The reaction site can be switched by changing the photocatalyst to TBADT, and the site‐selectivity is controlled by the steric hindrance between the bulkier TBADT photocatalyst and the substituents of the saccharides. The reaction is compatible with several electron‐deficient alkenes and saccharides, and provides C‐saccharides in good yields. Furthermore, the monoalkylated product was obtained in excellent yield, even on the gram scale, under TBADT photocatalysis. Applicability was demonstrated by site‐selective C(sp3)−H alkylation of glycosyl derivatives. The reactions proceed via a site‐selective hydrogen atom transfer between the photocatalyst and saccharide, and the generated carbon radical reacts with an electron‐deficient alkene to give alkylated products. [ABSTRACT FROM AUTHOR]

Although the functionalization and modification of single‐walled carbon nanotubes (SWCNTs) has been advanced for two decades, their chemical transformation via catalytic processes has yet to be explored and further facilitate their industrial utility. Here, the decatungstate‐photocatalyzed acylation is described of semiconducting (7,6)SWCNTs and the scope of the reaction is investigated by employing alkyl, aromatic, and organometallic aldehydes. The success of the methodology is confirmed by diverse spectroscopic, thermal, microscopy imaging, and redox techniques. The developed catalytic process for the functionalization of SWCNTs is environmetal friendly, since the catalyst and unreacted aldehydes can be recovered and reused, while the modified SWCNTs can be easily isolated and purified by membrane filtration. It is believed that the current findings will open new avenues for the catalytic functionalization of SWCNTs and the approach is intended to extend for modifying 2D nanomaterials. [ABSTRACT FROM AUTHOR]

We report herein a convenient and scalable dearomative hydroacylation reaction of indoles. Employing readily available aldehydes as the acyl source and TBADT as an inexpensive direct HAT photocatalyst, a variety of indoles derivatives were converted into synthetically interesting 2‐acylindolines in good to excellent yields as well as great diastereoselectivity under mild conditions. An asymmetric version of the reaction was successfully developed and an experimental mechanistic investigation was carried out in order to gain further insights on the assumed reaction pathway. [ABSTRACT FROM AUTHOR]

Compound [Ag44(W10O32)(StBu)24(CF3COO)8](CF3COO)6 ⋅ 6H2O (1) was synthesized through a one‐pot method. This is the first case of isolating a new silver thiolate cluster containing a [W10O32]6− template which transforms from WO42− polyoxoanion through a self‐assembly process. The anionic nature of the reduced [W10O32]6− template and the effective silver‐oxygen interaction contribute to the formation of the Ag44 nanowheel in 1. The luminescence, photocatalytic activity and electrochemistry properties of 1 were studied. [ABSTRACT FROM AUTHOR]

This article reveals that molybdenum (Mo) heteroatoms isomorphously substituted decatungstates (Mo–DTs) can be conveniently synthesized via copolymerization of tungstate and molybdate in acidic solution. A series of characterizations support that the incorporated Mo heteroatoms play crucial roles in improving the redox capacity and visible light harvesting efficiency of Mo–DTs, especially the photo‐excited probability and lifetimes, so that the novel Mo–DTs exhibit a remarkably enhanced photo‐catalytic efficiency in the visible‐light‐triggered selective oxidation of inert hydrocarbons by O2 under mild conditions. In the photo‐oxidation of cyclohexane under continuous visible light irradiation for 30 h, the best 1 % Mo–DT can achieve 44.8 % conversion and 89.7 % cyclohexanone selectivity in the presence of 2 M HCl, and the regenerated catalyst after simple hydrothermal treatment has excellent reusability. This is the first successful example of incorporating Mo atoms into the skeleton of non‐lacunary DTs, which has special significance for expanding the application of DTs in visible‐light‐catalysis. [ABSTRACT FROM AUTHOR]

A sunlight photocatalytic synthesis of aryl hydrazides was achieved via a decatungstate-promoted addition process of aromatic aldehydes to azo compounds. Aryl hydrazides can be produced in good to excellent yields under room temperature, even if the reaction was carried out as "window ledge" mode. This process is easy to be operated and no additional additives are needed, which makes the practicability and application value increase obviously. [ABSTRACT FROM AUTHOR]

Tetrabutylammonium decatungstate (TBADT) has emerged as a valuable photocatalyst for sunlight‐induced organic reactions. In this communication we wish to present its use for the photocatalytic oxidation of hydroxamic acids to generate fleeting nitrosocarbonyl intermediates. The reaction required a fine tuning of the conditions, especially in terms of solvent and additives, since an aqueous acetonitrile solution containing a mild base (NaHCO3) gave the best results. The obtained highly reactive nitrosocarbonyl species were then efficiently trapped with suitable dienes, such as cyclopentadiene and 1,3‐cyclohexadiene, to afford the corresponding Hetero Diels–Alder (HDA) cycloadducts in good yields. Dedicated photophysical experiments helped to elucidate the mechanistic scenario. [ABSTRACT FROM AUTHOR]

Abstract: A mild and selective C(sp3)−H aerobic oxidation enabled by decatungstate photocatalysis has been developed. The reaction can be significantly improved in a microflow reactor enabling the safe use of oxygen and enhanced irradiation of the reaction mixture. Our method allows for the oxidation of both activated and unactivated C−H bonds (30 examples). The ability to selectively oxidize natural scaffolds, such as (−)‐ambroxide, pregnenolone acetate, (+)‐sclareolide, and artemisinin, exemplifies the utility of this new method. [ABSTRACT FROM AUTHOR]

Synergistic control over the SH2 transition states of hydrogen abstraction exploiting polar and steric effects provides a promising cooperative strategy for site-selective C(sp3)−H functionalization using decatungstate anion photocatalysis. By using this photocatalytic approach, the C−H bonds of substituted lactones and cyclic ketones were functionalized selectively. In the remarkable case of 2-isoamyl 4-tert-butyl cyclohexanone ( 1 t) bearing five methyl, five methylene, and three methine C−H bonds, one methine C−H bond in the isoamyl tether was selectively functionalized. [ABSTRACT FROM AUTHOR]