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1.
J Org Chem ; 87(22): 15061-15070, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36321917

RESUMO

A regio- and chemoselective sulfonylation of propargyl alcohols with sulfinamides in 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) was developed. It provided straightforward and mild access to multi-substituted allenyl sulfones by using sulfinamides as the sulfonyl sources. This transformation was promoted by HFIP and did not require any catalysts or oxidants, which allowed for the successful conversion of various tertiary and secondary propargyl alcohols into allenyl sulfones in high yields.

2.
Appl Opt ; 58(19): 5159-5164, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31503609

RESUMO

Catenary optics has attracted much interest due to its unique properties in wave-front manipulation, field enhancement, and dispersion engineering. In this paper, the applications of catenary optics in the near-field lithography are studied. The catenary shaped nanostructures and tip-insulator-metal (TIM) structures are simultaneously utilized to increase the contrast ratio of the focal plane and to give rise to a sharp focusing focal spot with high intensity. Moreover, the full width at half-maximum of the focal spot maintains well below the diffraction limit. The proposed catenary TIM structure may improve the quality of near-field lithography and find applications in super-resolution near-field direct writing nano-lithography.

3.
Chem Commun (Camb) ; 59(97): 14431-14434, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37982153

RESUMO

Rhodium-catalyzed three-component C-H bond activation of aromatics with amides and aldehydes to synthesize amines was established. The addition of copper was found to be essential to ensure the high reactivity. The mechanistic studies indicated that key intermediates formed by the transmetallization between rhodium and copper could further promote the addition between 2-(pyridin-2-yl)-phenyl-metal species and imines. A series of densely substituted amines could be conveniently prepared by this one-step, three-component procedure from commercially available substrates via C-H bond activation with water as the only by-product.

4.
Org Lett ; 24(43): 8072-8076, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36287617

RESUMO

The isomerization of allylic alcohols to the corresponding carbonyl compounds is a well-established reaction in organic synthesis. However, 1,3-carbon migration is a quite challenging field, and thus transformation has remained elusive until now. Herein, we present the ruthenium-catalyzed intramolecular 1,3-aryl migrative isomerization, which provides a mild and environmentally friendly method to synthesize various ketones with high step- and atom-economy and broad substrate scope. Meanwhile, the Ru(III)-catalyzed C(sp3)-C(aryl) bond cleavage of unactivated allylic alcohols may serve as a heuristic paradigm for transition-metal-catalyzed C-C activation.

5.
Infect Drug Resist ; 15: 6641-6650, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386413

RESUMO

Purpose: The appropriate management of spinal tuberculosis (TB) is challenging for clinicians and the key to treat spinal TB. Surgery and long course anti-TB chemotherapy may not be necessary to all situations. This study aimed to characterize the clinical features and factors affecting treatment outcomes. Patients and Methods: A retrospective study of patients with spinal TB over a 5-year period at a teaching hospital in central China was conducted. Features of patients with spinal TB who received different treatment modalities and factors associated with patient outcomes at the end of chemotherapy were analyzed. Results: Forty-five patients (21 men and 24 women) with spinal TB were available for analysis. The mean age was 55.39 ± 14.94 years. The most common vertebral area involved was the lumbar (42.2%). The mean number of vertebrae involved was 2.20 ± 0.59. 27 patients (60.0%) received surgical treatment, of which 21 (77.8%) received radical surgical treatment. Thirty-five patients (77.8%) had achieved a favorable status. Statistically, there was no significant correlation between favorable status and surgery, but among 27 surgical patients with spinal tuberculosis, patients receiving radical surgery tended to achieve good prognosis (P = 0.010; odds ratio = 0.053; 95% confidence interval 0.006-0.493). Moreover, there was no significant difference between long course and short course of anti-TB chemotherapy in prognosis in different treatment modalities. Conclusion: Although the patients with spinal TB who needed surgical treatment often got a better prognosis when they had radical surgery, surgery was not actually a factor for the favorable outcomes of patients with spinal TB. In different treatment modalities, there was no additional benefit in longer anti-TB chemotherapy periods.

6.
Org Lett ; 24(2): 741-745, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-34989575

RESUMO

A highly regioselective and catalyst-free sulfonation of allylic alcohols with sulfinyl amides has been realized. Such a mix-and-go procedure provides a convenient approach to synthetically various allylic sulfones under mild reaction conditions. Furthermore, this novel reaction shows ample substrate scope and outstanding functional group tolerance and could also be scaled-up. Meanwhile, it is the first example that sulfinyl amides act as a powerful sulfur nucleophile in the reactions. 1,1,1,3,3,3-Hexafluoro-2-propanol (HFIP) as a solvent plays a critical role in allylic sulfonation.

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