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Photocatalyzed alkylsulfonylation of unactivated alkenes using DABCO. (SO2)2 and thianthrenium salts via a distal heteroaryl migration process has been developed, which provides a new means of synthesizing a variety of valuable alkylsulfonyl-substituted compounds. These alkylsulfonyl radicals couple with unactivated alkenes to undergo efficient intermolecular reactions, followed by distal heteroaryl migration. This mild catalytic method is tolerant of functional groups and affords medicinally relevant alkylsulfonylated heterocycles.

Nanomaterials have received increasing attentions owing to their potential hazards to the environment and human health; however, the multi-generational toxicity of graphene oxide under consecutive multi-generational exposure scenario still remains unclear. In the present study, Caenorhabditis elegans as an in vivo model organism was employed to explore the multi-generational toxicity effects of graphene oxide and the underlying mechanisms. Endpoints including development and lifespan, locomotion behaviors, defecation cycle, brood sizes, and oxidative response were evaluated in the parental generation and subsequent five filial generations. After continuous exposure for several generations, worms grew smaller and lived shorter. The locomotion behaviors were reduced across the filial generations and these reduced trends were following the impairments of locomotion-related neurons. In addition, the extended defecation cycles from the third filial generation were in consistency with the relative size reduction of the defecation related neuron. Simultaneously, the fertility function of the nematode was impaired under consecutive exposure as reduced brood sizes and oocytes numbers, increased apoptosis of germline, and aberrant expression of reproductive related genes ced-3, ced-4, ced-9, egl-1 and ced-13 were detected in exposed worms. Furthermore, the antioxidant enzyme, SOD-3 was significantly increased in the parent and filial generations. Thus, continuous multi-generational exposure to graphene oxide caused damage to the neuron development and the reproductive system in nematodes. These toxic effects could be reflected by indicators such as growth inhibition, shortened lifespan, and locomotion behavior impairment and induced oxidative response.

A green efficient photoredox-catalyzed decarboxylative alkynylation of carboxylic acids with alkynyl bromides has been developed. This broadly applicable protocol is presented wherein a-amino, aliphatic and α-oxy acids are converted into useful alkynylation products. The commercially-available organic photocatalyst 4CzIPN is used as the photocatalyst, organic base DBU is utilized as the base, and DMSO serves as solvent. This strategy features mild conditions, is metal-free, and is environmentally friendly. The batch and continuous-flow protocols described were applied to obtain a broader substrate scope of functionalization (more than 50 examples). Furthermore, we demonstrate that the use of microflow technology enhanced and intensified the reaction process, achieving significantly reduced reaction times (i.e., 10 min of residence time). [ABSTRACT FROM AUTHOR]