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A strategy for the formation of antimony‐carbon bond was developed by nickel‐catalyzed cross‐coupling of halostibines. This method has been applied to the synthesis of various triaryl‐ and diarylalkylstibines from the corresponding cyclic and acyclic halostibines. This protocol showed a wide substrate scope (72 examples) and was compatible to a wide range of functional groups such as aldehyde, ketone, alkene, alkyne, haloarenes (F, Cl, Br, I), and heteroarenes. A successful synthesis of arylated stibine 3 a in a scale of 34.77 g demonstrates high synthetic potential of this transformation. The formed stibines (R3Sb) were then used for the palladium‐catalyzed carbon–carbon bond forming reaction with aryl boronic acids [R−B(OH)2], giving biaryls with high selectivity, even the structures of two organomoieties (R and R′) are very similar. Plausible catalytic pathways were proposed based on control experiments. [ABSTRACT FROM AUTHOR]

Herein, decarboxylative C(sp 3 )-Sb coupling of aliphatic carboxylic acid derivatives with chlorostibines to access alkylstibines has been achieved. This catalyst-, ligand-, and base-free approach using zinc as a reductant affords various kinds of benzyldiarylstibines and other monoalkyldiarylstibines and tolerates various functional groups, including chlorine, bromine, hydroxyl, amide, sulfone, and cyano groups. The late-stage modification and the gram-scale experiments illustrate its potential application.

In this study, we present a nickel-catalyzed reductive C(sp 3 )-Sb coupling of unactivated alkyl chlorides with chlorostibines. This approach is highly versatile, tolerating various functional groups such as acetal, alkene, nitrile, amine, ester, silyl ether, thioether, and various heterocyclic compounds. Notably, the late-stage modification of bioactive molecules and the satisfactory anticancer activity against cancerous MDA-MB-231 also demonstrate the potential application.

The use of radiotherapy for hypopharyngeal cancer (HC) treatment is increasing, and it is currently the primary treatment option for this cancer. However, radioresistance occurs in a proportion of patients. Here, we found that radiation increased proteasomal gene expression and that proteasome assembly was dependent on the induction of transcription factor NRF1 in HC. Through screening assays, we identified a mechanism by which proteasome-mediated degradation of DEP domain-containing mTOR-interacting protein (DEPTOR) contributes to the elevation of mTORC1 signaling after radiation. Therefore, after treatment with proteasome inhibitors (PIs), stabilization of DEPTOR inhibited mTORC1 signaling elevated by radiation and ultimately sensitized HC to radiotherapy. Mechanically, PIs not only interrupted the deubiquitination and degradation of DEPTOR but also suppressed the ubiquitination of DEPTOR mediated by β-TrCP. Clinically, the high levels of DEPTOR in HC cells were associated with sensitivity to radiotherapy and favorable prognosis. Stabilizing DEPTOR through targeting proteasome-mediated degradation is a potential strategy for sensitizing HC to radiotherapy., Competing Interests: The authors declare no competing interests., (© 2022 The Authors.)

Copper-catalyzed oxidative intramolecular cyclization of o -alkylated anilines via cleavage of C(sp 3 )-H and N-H bonds for the production of indolines is described. This approach provides a straightforward strategy for the synthesis of nitrogen-containing heterocyclic compounds through the functionalization of unactivated C(sp 3 )-H bonds with high site selectivity. The present catalytic system shows high preference for functionalization of unactivated C(sp 3 )-H bonds over C(sp 2 )-H bonds, leading to C-N bond formation.

The reaction of trifluoroacetyl amides with Grignard reagent for the substitution of CF 3 group with various alkyl or aryl groups is described. A variety of aryl, quinolin-8-yl, and (hetero)alkyl functional groups as well as F, Cl, and Br atoms are well tolerated. These moisture-stable and easily available trifluoroacetyl amides can be conveniently obtained and used as new versatile precursors for isocyanates. The control experiments show that the reaction proceeds via an isocyanate intermediate and/or alkoxide/amide dual anionic intermediate.