نتایج جستجو برای: dihydropyrimidinones

تعداد نتایج: 100  

2001
Jiajian Peng Youquan Deng

3,4-Dihydropyrimidin-2(1H)-ones were synthesised in high yields by one-pot three-component Biginelli condensation in the presence of room temperature ionic liquids such as 1-n-butyl-3-methylimidazolium tetrafluoroborate (BMImBF4) or hexafluorophosphorate (BMImPF6) as catalysts under solvent-free and neutral conditions. © 2001 Elsevier Science Ltd. All rights reserved. Recently, the interest in ...

Mehdi Behvandi Behvandi Soheil Sayyahi,

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.

Mehdi Behvandi Behvandi Soheil Sayyahi,

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.

B. Pouramiri E. Tavakolinejad Kermany H. Khabazzadeh H. Khajesamani

An improved, simple, and facile synthesis of 3,4-dihydropyrimidin-2(1H)-ones by employing three-component, one-pot condensation reaction of β-keto ester, aromatic aldehydes, and urea or N-methylurea using LaCl3/ClCH2COOH as an inexpensive and green chemistry catalyst system under solvent-free conditions described. Compared with the classicalBiginelli reaction conditions, this method has the adv...

Hojjatollah Salehi

Simple and improved conditions have been found to carry out the Biginelli reaction for the synthesis of 3, 4-dihydropyrimidin-2(1H) - one derivatives. This synthesis was performed in the presence of 12-molybdophosphoric acid (H3PMo12O40) as catalyst. These reactions were performed under solvent free conditions with microwave irradiation as the energy source. Compared with the classical Biginell...

Gholam Reza Najafi Hakimeh Saeidiroshan Leila Moradi,

Multiwalled carbon nanotubes (MWCNTs) have been functionalized with -SO3H groups using new three steps chemical routes. Firstly, OH groups have been attached to CNT surfaces through a radical reaction. The second step involves converting the hydroxyl groups into the oxide one and last step included the attachment of –SO3H groups on the MWCNTs surfaces in the presence of 1-butyl-3-methyl imidazo...

An efficient synthesis route to 1,4-dihydropyrimidine derivatives from reaction of divergent aldehydes with ethylacetoacetate and urea under solvent-free conditions by ZnO nanoparticles as a relative in expansive, eco-friendly, easy available, non-volatile, non-explosion, thermally robust, recyclable and easy to handle catalyst at 90°C with excellent yields is described. Unenhanced reaction tim...

An efficient synthesis route to 1,4-dihydropyrimidine derivatives from reaction of divergent aldehydes with ethylacetoacetate and urea under solvent-free conditions by ZnO nanoparticles as a relative in expansive, eco-friendly, easy available, non-volatile, non-explosion, thermally robust, recyclable and easy to handle catalyst at 90°C with excellent yields is described. Unenhanced reaction tim...

Gholam Reza Najafi Hakimeh Saeidiroshan Leila Moradi,

Multiwalled carbon nanotubes (MWCNTs) have been functionalized with -SO3H groups using new three steps chemical routes. Firstly, OH groups have been attached to CNT surfaces through a radical reaction. The second step involves converting the hydroxyl groups into the oxide one and last step included the attachment of –SO3H groups on the MWCNTs surfaces in the presence of 1-butyl-3-methyl imidazo...

Ahmad Shaabani, Ayoob Bazgir Masoumeh Sharifi Kiasaraie Sakineh Arab Ameri Sima Samadi

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 importan...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید