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Luteolin (Lu), a compound with various biochemical and pharmacological activities beneficial to human health, has attracted researchers' attention. This study proposes an efficient and scalable method using ultrasound to intercalate graphene oxide (GO)-coated silica spheres (SiO2) into MXenes, resulting in a 3D conductive interconnected structural composite material. Characterization of the composite material was conducted using SEM, TEM, XRD, XPS, and Raman spectroscopy. MXenes exhibit excellent electrical conductivity, and the SiO2@GO surface with abundant hydroxyl and silanol groups provides high-binding active sites that facilitate Lu molecule enrichment. The formation of the 3D conductive interconnected structural composites enhances charge transport, significantly improving sensor sensitivity. Consequently, the sensor demonstrates excellent detection capabilities (detection range 0.03–7000 nM, detection limit 12 pM). Furthermore, the sensor can be applied to quantitative determination of Lu in real samples, including chrysanthemums, Jiaduobao, honeysuckle, purple perilla, and peanut shells, achieving recoveries between 98.2 and 104.7%. [ABSTRACT FROM AUTHOR]

[Display omitted] • Metal-free. • C H functionalization. • Good functional group tolerance. • Multistep cascade reaction. The efficient synthesis of sulfonated naphthols was realized by dehydroaromatization of β-tetralones with sodium sulfinates under metal-free conditions. Iodine-containing reagents played an important role in this oxidative coupling process. Sodium sulfinates served as a stable and readily available sulfur source, providing sulfones in good to excellent yields. A wide range of functional groups were well tolerated in this reaction. [ABSTRACT FROM AUTHOR]

A novel ratiometric fluorescent probe HB‐2 based on benzothiazole for hypobromous acid (HBrO) was synthesized and studied. After HBrO was added to the CH3CN‐HEPES solution of the HB‐2, the probe cyclized to form a sulfimine bond, which increased the conjugated degree of the system. The fluorescence emission peak of the reaction system at 447 nm gradually decreased, while the newly generated emission peaks gradually increased at 580 nm. The ratio of the fluorescence intensity at the two wavelengths of 447 nm and 580 nm increased about 234 times. Moreover, it has successfully been used to stain and record microscopy images of 4T1 cells, and the presence of exogenous HBrO could be judged by the change of fluorescence intensity. [ABSTRACT FROM AUTHOR]

The synthesis of sulfur heterocycles via the construction of C–S bonds has received considerable attention due to their biological value and extensive pharmaceutical application. While diverse sulfurating agents have been developed over the past few decades, in this regard, elemental sulfur, with advantages of low toxicity, odorless nature and chemical stability, has great potential for the construction of diverse sulfur heterocycles through its direct incorporation into the target molecules in a concise way. Direct functionalization of inert C–H bonds can shorten the number of reaction steps and minimize the amount of waste formed. Hence, heteroannulations via direct C–H sulfuration is considered to be an attractive strategy for the synthesis of sulfur heterocycles. In the last few years, a vast array of concise systems have been reported for the synthesis of some valuable sulfur heterocycles such as thiophenes, thienoindoles, thienothiazoles, thiazoles, benzothiazoles, and thiadiazoles through direct C–H sulfuration/annulations with elemental sulfur. These are discussed in detail in this review. 1 Introduction 2 Thiophenes 3 Thienoindoles 4 Thienothiazoles 5 Other Fused Thiophenes 6 Thiazoles 7 Benzothiazoles 8 Thiadiazoles 9 Others 10 Summary and Outlook [ABSTRACT FROM AUTHOR]

The synthetic methodology for direct indole functionalizations is of great significance in indole chemistry and has been intensively investigated in the last few decades. From the perspective of green chemistry, oxygen is the best choice as the terminal oxidant in molecular synthesis. Hence, aerobic oxidative functionalization of indoles became a hot research topic in the last decade. Numerous efficient protocols in this field have been discovered that enable facile and efficient transformations of indoles to related valuable compounds, which are summarized and discussed in detail in this review. [ABSTRACT FROM AUTHOR]

An efficient and convenient strategy for the preparation of diaryl sulfides via a Fe‐promoted direct sulfuracylation of 2‐naphthylamine using thioesters as bifunctional reagents is described. This synthetic strategy features high chemoselectivity, good substrate scope and functional group tolerance. [ABSTRACT FROM AUTHOR]

The palladium-catalyzed desulfinative iodination of sodium sulfinates and sulfonyl hydrazides with KI or I2 is described. The reaction proceeds smoothly under mild conditions using O2 or air as an environmentally benign oxidant. [ABSTRACT FROM AUTHOR]

An iodine-catalyzed sulfenylation of free indoles with sodium sulfinates is described. The reaction selectively afforded 3-arylthioindoles in good to high yields in anisole under metal-free conditions. Functional groups such as halogens were well tolerated under the optimized reaction conditions. [ABSTRACT FROM AUTHOR]

Abstract: A convenient and efficient method for the synthesis of 2-acylbenzothiazoles from benzothiazoles and aromatic ketones using oxygen as oxidant is described. FeCl3·6H2O showed the best reactivity among the various iron salts investigated. Various functional groups were well tolerated under the optimized reaction conditions. [Copyright &y& Elsevier]

An iron-catalyzed arylation of azoles with aromatic aldehydes using oxygen as oxidant has been discovered. The reaction proceeded well for a range of different substrates under oxidative conditions. [ABSTRACT FROM AUTHOR]

The first palladium-catalyzed diarylamine formation from nitroarenes and cyclohexanone derivatives using borrowed hydrogen is described. Various diarylamines were selectively obtained in good to excellent yields. The reaction tolerated a wide range of functionalities. The nitro reduction, cyclohexanone dehydrogenation, and imine formation and reduction were realized in a cascade without an external reducing reagent and oxidant. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed desulfitative hydroarylation of alkynes with aryl sulfinic acid sodium salts is described. The reaction showed good regio- and stereoselectivity, and afforded the hydroarylation products in good yields. Various functional groups were well tolerated under the optimized reaction conditions. [ABSTRACT FROM AUTHOR]

An esterification and amination of benzylic C–H bonds was developed by using 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) under metal- and iodide-free conditions. Both carboxylic acids and amines could be used as ideal coupling partners for the oxidative coupling reactions with various diarylmethanes. A close to equal amount of coupling reagents was enough to afford the product in good to high yields. [ABSTRACT FROM AUTHOR]

A simple copper-catalyzed redox coupling of sodium sulfinates and nitroarenes is described. In this process, abundant and stable nitroarenes serve as both the nitrogen sources and oxidants, and sodium sulfinates act as both reactants and reductants. A variety of aromatic sulfonamides were obtained in moderate to good yields with broad substrate scope. No external additive is employed for this kind of transformation. [ABSTRACT FROM AUTHOR]

The Pd-catalyzed desulfinative iodination of sodium sulfinates and sulfonyl hydrazides is developed using either KI or iodine as reagent in the presence of air or oxygen as terminal oxidant. [ABSTRACT FROM AUTHOR]

An efficient procedure is elaborated for the hydroarylation of alkynes with sodium aryl sulfinates as aryl sources. [ABSTRACT FROM AUTHOR]

The reaction of benzothiazoles with acetophenones gives 2-acylbenzothiazoles (III) as sole products whereas propiophenone (IVa) and benzoylacetate (IVb) furnish a relevant amount of byproduct (V). [ABSTRACT FROM AUTHOR]

One aliphatic aldehyde, e.g. (IIb), is also included which gives the corresponding product (IIIb) in moderate yield. [ABSTRACT FROM AUTHOR]