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[17] In this context, the development of efficient and mild methods for indole borylation has attracted increasing attention for research on the preparation of complex indoles. Although the use of a 1-adamantanoyl group can provide the desired indole C-H borylation products with high reactivity and selectivity, removing the directing group requires additional steps (Figure 4). Keywords: C-H bond activation; borylation; indoles; BBr 3; site selectivity; metal-free reaction EN C-H bond activation borylation indoles BBr 3 site selectivity metal-free reaction 2220 2226 7 10/31/23 20231127 NES 231127 Graph The indole ring system is one the most common heterocycles, present in many natural products and pharmaceuticals. [22] C2-Borylated indoles are versatile synthetic intermediates used to build 2,3-disubstituted indole skeletons as key intermediates in total syntheses of natural products and pharmaceuticals (Figure 1 A). [Extracted from the article]

Metal‐catalyzed C−H activation strategies provide an efficient approach for synthesis by minimizing atom, step, and redox economy. Developing milder, greener, and more effective protocols for these strategies is always highly desirable to the scientific community. In this study, the utilization of a single rhodium complex enabled the visible‐light‐induced late‐stage C−H activation of biaryl‐type phosphines with alkynyl bromides, employing inherent phosphorus atoms as directing groups. This chemistry combines P(III)‐directed C−H activation with visible light photocatalysis, under exogenous photosensitizer‐free conditions, offering a unique platform for ligand design and preparation. Furthermore, this study also explores the asymmetric catalysis and coordination chemistry of the resulting P‐alkyne hybrid ligands with specific transition metals. Experimental results and density functional theory calculations demonstrate the mechanistic intricacies of this transformation. [ABSTRACT FROM AUTHOR]

Metal‐catalyzed C−H activation strategies provide an efficient approach for synthesis by minimizing atom, step, and redox economy. Developing milder, greener, and more effective protocols for these strategies is always highly desirable to the scientific community. In this study, the utilization of a single rhodium complex enabled the visible‐light‐induced late‐stage C−H activation of biaryl‐type phosphines with alkynyl bromides, employing inherent phosphorus atoms as directing groups. This chemistry combines P(III)‐directed C−H activation with visible light photocatalysis, under exogenous photosensitizer‐free conditions, offering a unique platform for ligand design and preparation. Furthermore, this study also explores the asymmetric catalysis and coordination chemistry of the resulting P‐alkyne hybrid ligands with specific transition metals. Experimental results and density functional theory calculations demonstrate the mechanistic intricacies of this transformation. [ABSTRACT FROM AUTHOR]

Described herein is a visible‐light photoredox‐catalyzed regioselective 1,4‐hydroalkylation of 1,3‐enynes. Various of di‐ and tri‐substituent allenes were really accessible under the present reaction conditions. The visible‐light photoredox activation of the carbon nucleophile to generate its radical species, allowing the addition with un‐activated enynes. The synthetic utility for the present protocol was demonstrated by a large‐scale reaction, as well as the derivatization of the allene product. [ABSTRACT FROM AUTHOR]

Water-soluble [3]pseudorotaxane with enhanced fluorescence emission was successfully constructed and applied in cell imaging and photodynamic cancer therapy. [ABSTRACT FROM AUTHOR]

Visible‐light mediated hydrophosphorylation and hydrophosphorylative cyclization reactions using heterogeneous graphitic carbon nitride as the photocatalyst were described. The phosphorus atom radical was generated and allows the radical addition and addition/cyclization sequence, efficiently resulting in the final phosphorylated alkenes and cycles formation. Recyclable, nontoxic and low‐cost heterogeneous graphitic carbon nitride as visible light photocatalyst provides a new opportunity for the hydrophosphorylation and hydrophosphorylative cyclization reactions under the present redox‐neutral conditions. [ABSTRACT FROM AUTHOR]

A three‐component acylation/peroxidation of alkenes through visible‐light photocatalysis was described. The acyl radical was generated by a hydrogen atom transfer process and enabled the radical addition and peroxidation. Various indole‐3‐carbaldehyde and styrene derivatives were subjected to the current visible light photochemical conditions, delivering β‐peroxy‐ketones in moderate to good isolated yields. [ABSTRACT FROM AUTHOR]

A "three‐components" supramolecular assembly has been fabricated by mixing 2, 2': 6', 2"‐terpyridine attached pillar[5]arene, cyano and triazole bearing alkyl chain and Zn2+ in solvent of CHCl3 and CH3CN. The driving forces for the assembly were believed to be host‐guest and metal chelating interactions as characterized by 1H NMR, UV‐vis and fluorescence spectra. The supramolecular organo‐gel formed upon the concentration of components amount to 1 M. The supramolecular displayed nitrobenzene based explosive sensing capability using picric acid, ortho‐nitrobenzene and phenol as samples. The assembly was most sensitive towards picric acid among the three analytes. The limit of detection for picric acid was determined to be 1.66 × 10−4 M. [ABSTRACT FROM AUTHOR]

• A medium-strength complex was formed between P5SB and MB. • The amphiphilic P5SB⊃MB complex assembled into stable vesicles at pH=7.4. • The anti-cancer efficiency of DOX-loaded P5SB⊃MB vesicles was significantly enhanced. • The live-cell imaging property of DOX was maintained after encapsulation. Cocktail therapy is one of the leading approaches for treating some complex diseases. Herein, a pH-triggered supramolecular cocktail drug delivery system assembled by the medium-strength complexes of pillar[5]arene-based Schiff base (P5SB) with methylene blue (MB). Molecular modeling suggest that noncovalent interactions between Schiff base side chain of P5SB and MB were mainly responsible for the stability of the complex. The amphiphilic P5SB⊃MB complex assembled into stable vesicles with an average diameter of 244.1 nm in conventional physiological environment (pH=7.4). Drug loading experiments demonstrated that doxorubicin (DOX) could be efficiently encapsulated into the hollow vesicles, and the drug would be rapidly released under acidic environment (pH=6.0). Moreover, the anti-cancer efficiency of DOX-loaded P5SB⊃MB vesicles was significantly enhanced because of the synergistic effect of P5SB, MB and DOX. Nonetheless, the live-cell imaging property of DOX was maintained after encapsulation. [Display omitted] [ABSTRACT FROM AUTHOR]