نتایج جستجو برای: 34 dihydropyrimidin 21h ones
تعداد نتایج: 236634 فیلتر نتایج به سال:
In this study, a variety of 3, 4-dihydropyrimidin-2(1H)-ones derivatives were synthesized via three-component Biginelli reaction. The quaternary ammonium- treated clay -catalyzed process proved to be simple, efficient, and environmentally friendly.
In this study, a variety of 3, 4-dihydropyrimidin-2(1H)-ones derivatives were synthesized via three-component Biginelli reaction. The quaternary ammonium- treated clay -catalyzed process proved to be simple, efficient, and environmentally friendly.
In this study, an efficient and green process for the synthesis of dihydropyrimidin-2(1H)-ones from aromatic benzaldehydes, ethyl acetoacetate and urea using Al-MCM-41 as heterogeneous catalyst and microreactor under solvent-free conditions has been developed. The advantages of this method are easy work-up procedure, regeneration of the catalyst, clean and neutral reaction conditions.
alkali and alkaline earth metals hydrogen sulfate catalyzed the one-pot three component condensation reactions of aldehydes, 1,3-dicarbonyl compounds and urea or thiourea under solvent-free conditions leading to 3,4-dihydropyrimidin-2(1h)-ones in high yields at 80 °c. our results showed that biginelli reaction not only is ph dependent, but the cation of catalyst plays an important role.
d-tartaric acid is successfully used as a green and efficient catalyst for the synthesis of 3,4-dihydropyrimidin-2(1h)-ones under solvent-free conditions. the developed method has many advantages, including devoid of harmful catalyst and solvents, high yield and easily work-up.
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