|
|
[求助]
翻译中文 有机合成
|
To investigate the effects of solvent, the condensation reaction of benzaldehyde, dimedone, ethylacetoacetate, and ammonium acetate in various organic solvents at room temperature using 4.85 wt.% Ni0-nanoparticles as the catalyst was carried out. About 75% of the expectedproduct 4a was obtained when the solvent was ethanol. Obviously, thepolar solvents such as ethanol and acetonitrile [Table 2] were much better than non polar solvents. It was observed that in the presence ofsolvent the reaction takes more time to give high yields of product under similar ratio of the reactants. This may be due to the competitive adsorption of the solvent with the substrate molecule on the catalyst surface; hence reaction under solvent-free condition gives better yields in less time. The model reaction was carried out without any catalyst,but the product formation was in poor yield. Therefore, the catalyst plays an important role in the success of the reaction in terms of rate and yields of Hantzsch polyhydroquinoline derivatives. The reaction was also investigated with acid activated Mont. alone as catalyst and only a negligible amount of product formation was observed. Therefore, it is evident that supported Ni0 -nanoparticles are the active sites. |
|
回复此楼
申请26博士
已经有5人回复