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731.
Recent synthesis of sp-hybridized cyclo[18]carbon allotrope has attracted immense curiosity. Since then, a generous amount of theoretical studies concerning aromaticity, adsorption, and spectra of the molecule have been performed. However, very few stuides have been carried out concerning its reactivities and catalytic behaviour. In this article, a DFT-based inquisition has been reported regarding the reactivity of Si substituted cyclo[18]carbon molecule towards molecular N2. Results show that the Si substituted derivative is effective in producing adducts with molecular nitrogen. Charge calculations and IRC trapping methods indicate that only the Si center of C17Si and its (HOMO-1) level participate in N2 addition. The N-adduct so formed, is then found to spontaneously react with molecular H2. The addition of two H2 molecules to the activated nitrogen molecule to give respective amine derivatives have also been studied. The successful generation of the precursor of NH3 by C17Si lays a clear emphasis on its potentiality. 相似文献
732.
Density functional theory has been used to elucidate the mechanistic underpinnings of the regeneration of ammonia-borane (H3B−NH3, AB ) from polyborazylene (BxNxHx, PBz ) in the presence of hydrazine (H2N−NH2, Hz ). Herein, borazine (B3N3H6, Bz ) is used as the simplest relevant model of PBz for the regeneration process. Digestion of Bz using Hz was found to occur by a string of Lewis acid base adduct (between B atoms of Bz and Hz molecule) formation and Hz assisted proton transfer processes. Later, B−H bonds of HB(NHNH2)2, the Bz digested product, are redistributed to form hydrazine-borane (H3B−NH2NH2, HzB ) and B(NHNH2)3. Redistribution of B−H bonds occurs through hydroboration and concerted proton-hydride transfer. Another B−H redistributed product, B(NHNH2)3, produces HzB as a result of proton and hydride transfer from cis-diazene ( Dz ), the oxidized product of Hz in presence of O2. 相似文献
733.
Dr. Umme Tamima Dr. Sourav Sarkar Dr. Md Reyazul Islam Anushree Shil Dr. Kyeong Hwan Kim Dr. Ye Jin Reo Dr. Yong Woong Jun Hasanul Banna Soobin Lee Prof. Kyo Han Ahn 《Angewandte Chemie (International ed. in English)》2023,62(15):e202300580
Fluorescence monitoring of ATP in different organelles is now feasible with a few biosensors developed, which, however, show low sensitivity, limited biocompatibility, and accessibility. Small-molecule ATP probes that alleviate those limitations thus have received much attention recently, leading to a few ATP probes that target several organelles except for the nucleus. We disclose the first small-molecule probe that selectively detects nuclear ATP through reversible binding, with 25-fold fluorescence enhancement at pH 7.4 and excellent selectivity against various biologically relevant species. Using the probe, we observed 2.1–3.3-fold and 3.9–7.8-fold higher nuclear ATP levels in cancerous cell lines and tumor tissues compared with normal cell lines and tissues, respectively, which are explained by the higher nuclear ATP level in the mitosis phase. The probe has great potential for studying nuclear ATP-associated biology. 相似文献
734.
In this work, the anion-responsive conduct of a Ru(II)-bipyridine complex incorporating pyrazolyl-bis (benzimidazole) ligand is thoroughly investigated in acetonitrile and water via absorption and emission spectroscopy as well as by square-wave voltammetry (SWV). Substantial alteration of the photo-redox behavior of the complex is observed in the presence of the selected anions. The free form of the complex exhibits emission indicating the “on-state”, while inclusion of anions leads to quenching of emission and represents the “off-state”. The restoration of the initial state of the complex is feasible in the presence of acid and the process is reversible and can be recycled. In essence, the complex functions as anion- and acid-responsive molecular switches. Additionally, we applied herein neural network based deep learning methodologies, viz. Artificial Neural Networks (ANNs) and Adaptive Neuro-Fuzzy Inference System (ANFIS)} for thorough analysis and fully understand the multi-channel anion sensing behavior of the complex. 相似文献