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1.
J Am Chem Soc ; 146(23): 16295-16305, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38816788

RESUMO

Atomically precise metal nanoclusters (NCs) have become an important class of catalysts due to their catalytic activity, high surface area, and tailored active sites. However, the design and development of bond-forming reaction catalysts based on copper NCs are still in their early stages. Herein, we report the synthesis of an atomically precise copper nanocluster with a planar core and unique shell, [Cu45(TBBT)29(TPP)4(C4H11N)2H14]2+ (Cu45) (TBBT: 4-tert-butylbenzenethiol; TPP: triphenylphosphine), in high yield via a one-pot reduction method. The resulting structurally well-defined Cu45 is a highly efficient catalyst for the hydroboration reaction of alkynes and alkenes. Mechanistic studies show that a single-electron oxidation of the in situ-formed ate complex enables the hydroboration via the formation of boryl-centered radicals under mild conditions. This work demonstrates the promise of tailored copper nanoclusters as catalysts for C-B heteroatom bond-forming reactions. The catalysts are compatible with a wide range of alkynes and alkenes and functional groups for producing hydroborated products.

2.
Chemistry ; 30(23): e202302927, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38573029

RESUMO

A new cross-coupling of trifluoromethyl arenes has been realized via multiphoton photoredox catalysis. Trifluoromethyl arenes were demonstrated to undergo selective mono-defluorinative alkylation under mild reaction conditions providing access to a series of valuable α,α-difluorobenzylic compounds. The reaction shows broad substrate scope and general functional group tolerance. In addition to the electron-deficient trifluoromethyl arenes that are easily reduced to the corresponding radical anion, more challenging electron-rich substrates were also successfully applied. Steady-State Stern-Volmer quenching studies indicated that the trifluoromethyl arenes were reduced by the multiphoton excited Ir-based photocatalyst.

3.
Chem Commun (Camb) ; 60(39): 5153-5156, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38639139

RESUMO

We have developed a novel Ni-catalyzed reductive cross-coupling reaction of aryl bromides and alkyl iodides via a photoactive electron donor-acceptor (EDA) complex. This photo-induced process enables the efficient construction of C(sp2)-C(sp3) bonds in the absence of an external photocatalyst. Electronically and structurally diverse aryl bromides, as well as secondary and primary alkyl iodides could undergo this transformation smoothly. Natural product derivatives were employed successfully, and UV-vis spectroscopy was utilized to gain mechanistic insight.

4.
Cureus ; 16(4): e58987, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38800163

RESUMO

Background Communication is essential in the medical sector, particularly in the emergency departments (ED), to provide appropriate patient care. Lack of patient history and large patient numbers, cultural variations, inadequate health literacy, and language difficulties can impact effective communication. Aim This study aims to examine language and communication barriers experienced by ED physicians in Makkah, Saudi Arabia, as well as to determine the effect of language barriers on patient care and explore possible methods to deal with language and communication barriers. Methods This cross-sectional study was conducted from April 8 to June 6, 2023. A total of 136 responses were collected from ED physicians at the six Ministry of Health Hospitals (MOH) in Makkah through a validated online survey. The data analysis was implemented using RStudio (R version 4.1.1). Result In this study, 136 participants' data were examined. Of note, one-quarter of ED physicians (25%; n=34) under study stated that they always experienced language barriers, whereas 64.7% (n=88) of them sometimes experienced these difficulties. More than half of the ED physicians (54.4%; n=74) stated that their patients had poor outcomes because of poor communication. Among those who responded positively to poor outcomes, ED physicians' suggestions to improve communication with patients included providing labels of the common scientific terminologies in different languages (59.6%; n=81) and providing courses to communicate in foreign languages (48.5%; n=66). Conclusion Exposure to language barriers among ED physicians in Makkah was slightly high. This may impact the patient's outcomes. Therefore, strategies to improve patient-physician communication are needed.

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