In this study, we introduce a novel intramolecular hydrogen atom transfer (HAT) reaction that efficiently yields azetidine, oxetane, and indoline derivatives through a mechanism resembling the carbon analogue of the Norrish-Yang reaction. This process is facilitated by excited triplet-state carbon-centered biradicals, enabling the 1,5-HAT reaction by suppressing the critical 1,4-biradical intermediates from undergoing the Norrish Type II cleavage reaction, and pioneering unprecedented 1,6-HAT reactions initiated by excited triplet-state alkenes. We demonstrate the synthetic utility and compatibility of this method across various functional groups, validated through scope evaluation, large-scale synthesis, and derivatization. Our findings are supported by control experiments, deuterium labeling, kinetic studies, cyclic voltammetry, Stern-Volmer experiments, and density functional theory (DFT) calculations.

A series of polymers with both high refractive index and high Abbe number have been successfully synthesized through the photoclick thiol-ene reaction between the monomers derived from biobased magnolol (or honokiol) and commercial mercaptans and thiophenols. The polymer films not only exhibit a high refractive index and a high Abbe number but also display a transmittance of up to 90% in a range of wavelengths from 550 to 2000 nm and nearly 0% in the UV region. Moreover, these polymers also display low haze values in the visible-light region as well as exhibit good thermostability. These data indicate that they have potential applications for the fabrication of optical lenses and anti-UV coatings. In particular, this series of polymers are readily used for industrialization due to its excellent optical properties but low expense, simplicity, and efficiency of synthesis.

This work presents a novel strategy for postmodifying probes using dynamic covalent chemistry. Leveraging reversible interactions between boronic acid and diols, we obtained a panel of F-19-labeled probes with distinct resolving abilities. This approach enables rapid identification of probes with satisfactory performance, streamlining synthesis, and enhancing efficiency in chiral analysis. Our findings demonstrate an exceptional ability to differentiate compounds with distal chirality and challenging aliphatic amines. The postmodified probes also exhibit accuracy and reliability in determining enantiomeric excess, promising advancements in enantio-analysis techniques and chiral discrimination.

Roxarsone (ROX) is a commonly used antibacterial and growth-promoting additive to animal feed. The development of an effective method for detecting ROX and its conversion products is of importance because of their potential harm to human health and ecosystem. Herein, we report the designed synthesis of a novel one-dimensional covalent organic framework (1D COF), named EP-COF, and its application as a fluorescent probe for ROX sensing. EP-COF is constructed based on imine linkages, exhibiting high crystallinity, strong fluorescence emission, and good dispersibility in water. It displays a remarkable capability to efficiently detect ROX, with an impressive detection limit of 4.5 nmol/L. Moreover, EP-COF also offers advantages of excellent selectivity, and high structural stability. This work not only presents a promising approach for the detection of harmful substances like ROX, but also serves as a valuable reference for exploring application of 1D COFs in chemical sensing. (c) 2024 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.

The fluorosulfonyldifluoromethylation of unactivated alkenes and (hetero)arenes with iododifluoromethanesulfonyl fluoride (ICF2SO2F) under visible light photoredox catalysis was successfully developed. Key to the successful fluorosulfonyldifluoromethylation of aromatic compounds was the usage of AgOTf as an additive to promote the formation of the CF2SO2F radical. The protocol provided a straightforward way to introduce the interesting and useful CF2SO2F group on sp(3) and sp(2) carbons.

A copper-catalyzed arylation or alkenylation of quinoline N-oxides with aryl- or alkenylboronates, respectively, has been developed, which provides an efficient route for C2-substituted oxygenated quinolines under mild reaction conditions. The reaction shows a broad substrate scope for both quinoline N-oxides and aryl/alkenylboronates, mild reaction conditions, and high reaction efficiency. The formation of an aryl- or alkenyl-copper species as the key intermediate was suggested to be involved in this reaction.

Herein we report a photoredox/nickel-catalyzed cross-coupling of aryl bromides with 1,1,1,3,3,3-hexafluoroisopropanol for the construction of hexafluoroisopropyl aryl ethers. The mild reaction conditions employed allow for the applicability of a wide range of aryl and heteroaryl bromides. Late-stage functionalization and preliminary mechanistic studies have been demonstrated.

Herein, we report an effective approach for the synthesis of phenylethanoid glycosides bearing a fused 1,4-dioxane motif, employing a bio-inspired oxidative cyclization of the glucose 2 '-OH and benzylic carbon of phenylethanol aglycone as a key step. Thus, crenatoside (1), isocrenatoside (2), and 20 analogs with varied substitution on the peripheral phenyl rings are synthesized. Some of the synthetic glycosides show considerable anti-inflammatory and immunosuppressive activities, and compound 36 exhibited the most potent immunosuppressive activity, with an IC50 value of 19.9 mu M on B lymphocyte proliferation responses. Herein, we report an effective approach for the synthesis of phenylethanoid glycosides bearing a fused 1,4-dioxane motif, employing a bio-inspired oxidative cyclization of the glucose 2 '-OH and benzylic carbon of phenylethanol aglycone as a key step.

(Z)-1,2-Disubstituted, trisubstituted, and tetrasubstituted alkenes are not only important units in medicinal chemistry, natural product synthesis, and material science but also useful intermediates in organic synthesis. Development of catalytic stereoselective transformations to access multisubstituted alkenes with various substitution patterns from easily accessible modular starting materials and readily available catalysts is a crucial goal in the field of catalysis. Water is an ideal hydrogen source for catalytic transfer hydrogenation despite of the high difficulty to activate water. Here, we report a cobalt-catalyzed protocol for regio- and stereoselective transfer semihydrogenation of 1,3-dienes to construct a broad scope of (Z)-1,2-disubstituted, (Z)-, (E)-trisubstituted, and tetrasubstituted alkenes in high stereoselectivity with H2O as the hydrogen source. Mechanistic studies revealed that the reactions proceeded through a unique Co(I)/Co(III) cycle and involved a 1,4-cobalt shift process, which is an unprecedented reaction pathway, providing a new platform for modular synthesis of multisubstituted alkenes as well as opportunities for designing novel reaction modes and pushing forward the advancement in organocobalt chemistry.