DSpace Community:
https://dspace.ewha.ac.kr/handle/2015.oak/171803
2024-03-29T12:05:15Z
2024-03-29T12:05:15Z
[RhCp*Cl2]2-Catalyzed Indole Functionalization: Synthesis of Bioinspired Indole-Fused Polycycles
Akhilesh Kumar
https://dspace.ewha.ac.kr/handle/2015.oak/266368
2024-03-18T16:32:17Z
2023-01-01T00:00:00Z
Title: [RhCp*Cl2]2-Catalyzed Indole Functionalization: Synthesis of Bioinspired Indole-Fused Polycycles
Ewha Authors: Akhilesh Kumar
Abstract: Polycyclic fused indoles are ubiquitous in natural products and pharmaceuticals due to their immense structural diversity and biological inference, making them suitable for charting broader chemical space. Indole-based polycycles continue to be fascinating as well as challenging targets for synthetic fabrication because of their characteristic structural frameworks possessing biologically intriguing compounds of both natural and synthetic origin. As a result, an assortment of new chemical processes and catalytic routes has been established to provide unified access to these skeletons in a very efficient and selective manner. Transition-metal-catalyzed processes, in particular from rhodium(III), are widely used in synthetic endeavors to increase molecular complexity efficiently. In recent years, this has resulted in significant progress in reaching molecular scaffolds with enormous biological activity based on core indole skeletons. Additionally, Rh(III)-catalyzed direct C-H functionalization and benzannulation protocols of indole moieties were one of the most alluring synthetic techniques to generate indole-fused polycyclic molecules efficiently. This review sheds light on recent developments toward synthesizing fused indoles by cascade annulation methods using Rh(III)-[RhCp*Cl2]2-catalyzed pathways, which align with the comprehensive and sophisticated developments in the field of Rh(III)-catalyzed indole functionalization. Here, we looked at a few intriguing cascade-based synthetic designs catalyzed by Rh(III) that produced elaborate frameworks inspired by indole bioactivity. The review also strongly emphasizes mechanistic insights for reaching 1-2, 2-3, and 3-4-fused indole systems, focusing on Rh(III)-catalyzed routes. With an emphasis on synthetic efficiency and product diversity, synthetic methods of chosen polycyclic carbocycles and heterocycles with at least three fused, bridged, or spiro cages are reviewed. The newly created synthesis concepts or toolkits for accessing diazepine, indol-ones, carbazoles, and benzo-indoles, as well as illustrative privileged synthetic techniques, are included in the featured collection. © 2023 The Authors. Published by American Chemical Society.
2023-01-01T00:00:00Z
Aspects of luminescence nanoprobes for thermometry: Progress and outlook
Madhumita Patel
https://dspace.ewha.ac.kr/handle/2015.oak/266241
2024-03-11T16:31:57Z
2023-01-01T00:00:00Z
Title: Aspects of luminescence nanoprobes for thermometry: Progress and outlook
Ewha Authors: Madhumita Patel
Abstract: The measurement of correct temperature with precise accuracy is crucial to conduct both scientific research and industrial manufacturing. A conventional thermometer is based on the thermal expansion of materials and Seebeck effect. Therefore, conventional thermometers are not considered to be accurate for measuring the temperature at submicrometric spatial resolution. An urge for an innovative non-contact thermometer sensor encourages the development of luminescence thermometry as an attractive alternative for sensing and monitoring the temperature with high accuracy and preciseness. In this context, luminescence thermometry has emerged as an attractive field of research due to the exceptional properties of luminescent materials and its use in various applications of as-designed luminescence thermometry in chemistry, biomedicine, or electromagnetism. The present review summarizes the recent advances in developing, designing, and constructing luminescence thermometry using novel luminescent materials. The significance of luminescence thermotropy is discussed and described. Various effects of temperature on photoluminescence (PL) features and their detection modes are discussed. The review covers the different luminescent materials used for temperature sensing or thermometry; lanthanides doped materials, quantum dots, core@shell nanomaterials. organic fluorophores, hybrid nanomaterials. Conclusively, this review provides new direction to identify appropriate luminescent materials for luminescence thermometry. © 2023
2023-01-01T00:00:00Z
Molecular docking and dynamic simulations of 2-phenoxyaniline and quantum computational, spectroscopic, DFT/TDDFT investigation of electronic states in various solvents
Akhilesh Kumar
https://dspace.ewha.ac.kr/handle/2015.oak/266239
2024-03-18T16:32:09Z
2023-01-01T00:00:00Z
Title: Molecular docking and dynamic simulations of 2-phenoxyaniline and quantum computational, spectroscopic, DFT/TDDFT investigation of electronic states in various solvents
Ewha Authors: Akhilesh Kumar
Abstract: 2-phenoxyanline was thoroughly examined using several spectroscopy nuclear magnetic resonance, IR, UV–vis, and quantum mechanical methodologies. D F T with basis set is employed to determine structural optimization and distinct vibration modes. The optimum binding parameters agree closely with the observed binding characteristics. VEDA performed the duties relating to potential energy distribution (PED) satisfactorily. The G I A O approach was adopted to compute chemical shifts in the 13C, 1H- N.M.R and the outcomes were compared to experimental spectra. TD-DFT with PCM model was used to calculate UV–vis with different solvents that, when assessed against observational spectra. The FMO energy provides sufficient proof of such. Molecular docking and dynamic simulations gave a better idea of the interaction of ligands with receptors. © 2023 The Author(s)
2023-01-01T00:00:00Z
Design, Synthesis, and Applications of a Vanadium Complex: An Effective Catalyst for the Direct Conversion of Alcohols and Aldehydes to Esters
Akhilesh Kumar
https://dspace.ewha.ac.kr/handle/2015.oak/265495
2024-03-18T16:32:28Z
2023-01-01T00:00:00Z
Title: Design, Synthesis, and Applications of a Vanadium Complex: An Effective Catalyst for the Direct Conversion of Alcohols and Aldehydes to Esters
Ewha Authors: Akhilesh Kumar
Abstract: A novel bench-stable V-catalyst [(L2)VIVO](ClO4) was synthesized and characterized by X-ray diffraction (XRD) analysis and FT-IR, UV-visible, and EPR spectroscopies, which confirmed its excellent catalytic activity. In application, aldehydes are rapidly converted into their corresponding esters without additives in a one-pot manner using a newly developed catalyst [(L2)VIVO](ClO4) and H2O2 as a green oxidant. The developed method is compatible with a broad range of densely substituted aldehydes and allows for the facile preparation of aliphatic, aromatic, and heterocyclic esters, including esters derived from CD3OD, methanol, ethanol, iso-propanol, n-butanol, sec-butyl alcohol, and propargylic alcohol. Gratifyingly, numerous alcohols also directly converted to their corresponding esters in a one-pot manner. We disclose herein the direct conversion of two different functionalities (alcohols and aldehydes) into esters (33 examples) with satisfactory yields, showing the potential of the developed catalyst toward varied oxidative organic transformations in a one-pot manner. © 2023 American Chemical Society.
2023-01-01T00:00:00Z