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Nanoscale graphene oxide sheets as highly efficient carbocatalysts in green oxidation of benzylic alcohols and aromatic aldehydes
, Article Cuihua Xuebao/Chinese Journal of Catalysis ; Volume 38, Issue 4 , 2017 , Pages 745-757 ; 02539837 (ISSN) ; Heidari, M ; Akhavan, O ; Sharif University of Technology
Science Press
2017
Abstract
Nanoscale graphene oxide (NGO) sheets were synthesized and used as carbocatalysts for effective oxidation of benzylic alcohols and aromatic aldehydes. For oxidation of alcohols in the presence of H2O2 at 80 °C, the NGOs (20% mass fraction) as carbocatalysts showed selectivity toward aldehyde. The rate and yield of this reaction strongly depended on the nature of substituents on the alcohol. For 4-nitrobenzyl alcohol, <10% of it was converted into the corresponding carboxylic acid after 24 h. By contrast, 4-methoxybenzyl alcohol and diphenylmethanol were completely converted into the corresponding carboxylic acid and ketone after only 9 and 3 h, respectively. The conversion rates for...
N-doped CNT nanocatalyst prepared from camphor and urea for gas phase desulfurization: experimental and DFT study
, Article Journal of the Taiwan Institute of Chemical Engineers ; Volume 85 , April , 2018 , Pages 121-131 ; 18761070 (ISSN) ; Banna Motejadded, H ; Rashidi, A ; Hamzehlouyan, T ; Yousefian, Z
Taiwan Institute of Chemical Engineers
2018
Abstract
In the present work, mesoporous nitrogen-doped carbon nanotubes (N-CNTs) were synthesized by using a low-cost and unique set of precursors (camphor and urea). The CVD method at 1000 °C was used with different camphor/urea ratios, and Co-Mo/MgO nanocatalyst was utilized as growth catalyst. Application of mesoporous N-CNTs in selective oxidation of H2S was studied experimentally and N-CNTs interactions with H2S was also investigated using DFT calculations. The as-synthesized N-CNTs were characterized using FTIR, FE-SEM, elemental analysis, X-ray diffraction (XRD), XPS and nitrogen adsorption/desorption. The N-CNT2 sample with urea to camphor ratio (U/C) of 1 showed the highest sulfur yield at...
Enzyme-inspired lysine-modified carbon quantum dots performing carbonylation using urea and a cascade reaction for synthesizing 2-benzoxazolinone
, Article ACS Catalysis ; Volume 11, Issue 17 , 2021 , Pages 10778-10788 ; 21555435 (ISSN) ; Kalhor, H. R ; Sharif University of Technology
American Chemical Society
2021
Abstract
Catalysts as the dynamo of chemical reactions along with solvents play paramount roles in organic transformations in long-lasting modes. Thus, developing effective and biobased catalysts in nontoxic solvents is highly in demand. In this report, carbon quantum dots (CQDs) functionalized with-lysine (Lys-CQDs) were generated from entirely nature-derived materials; they were demonstrated to be a promising catalyst for C-N bond formation in choline chloride urea (ChCl/U), a natural deep eutectic solvent (NADES). Among a number of synthesized CQDs, Lys-CQD turned out to be a powerful catalyst in the model reaction with aniline to afford phenyl urea. This type of transformation is important...