使用4-(4-丙基哌嗪-1-基)丁烷-1-磺酸改性的二氧化硅描述了一种温和,简单,有效的方法来制备水介质中的巴比妥酸和吡喃并[2,3- d ]嘧啶衍生物包覆的磁性纳米颗粒可作为新型可重复使用的催化剂。通过使用外部磁体的磁倾析,可以容易地从反应混合物中分离出催化剂,并且在不显着降低活性的情况下重复使用至少八次。
the reaction of barbituric or thiobarbituric acid, malononitrile and aldehydes in the presence of this reagent and 1,4-disulfo-1,4-diazabicyclo[2.2.2]octane-1,4-diium chloride ([DABCO](SO3H)2(Cl)2) has been investigated. The structure of the products was characterized using IR, 1H NMR and 13C NMR spectroscopy. The present methodologies suggests several advantages such as ease of the preparation and
一种新的,直接的方法,可通过使用1,4-二磺基-1,4-二氮杂双环[2.2.2]辛烷-1通过巴比妥酸及其硫代类似物与醛的反应来合成5-芳基巴比妥酸和硫代巴比妥酸,已经报道了作为有效催化剂的4-二硫酸氢二钠([DABCO](SO 3 H)2(HSO 4)2)。在该项目中,还通过在该试剂和1,4-二磺基-1,4-二氮杂双环[2.2]存在下,通过巴比妥酸或硫代巴比妥酸,丙二腈和醛的反应制备吡喃并[2,3- d ]-嘧啶二酮。 .2]辛烷-1,4-氯化铵([DABCO](SO 3 H)2(Cl)2)已被调查。使用IR,1 H NMR和13 C NMR光谱对产物的结构进行表征。本方法论提出了若干优点,例如易于制备和处理催化剂,高收率,简单和绿色的方法,低成本,短的反应时间,易于后处理和在水中作为绿色溶剂进行反应的预形成。
Succinimidinium hydrogensulfate ([H-Suc]HSO4) as an efficient ionic liquid catalyst for the synthesis of 5-arylidenepyrimidine-2,4,6(1H,3H,5H)-trione and pyrano-pyrimidinones derivatives
this work, succinimidinium hydrogensulfate ([H-Suc]HSO4), a newly reported Brönsted acidic ionic liquids is used as an efficient, homogeneous and reusable catalyst for the synthesis of 5-arylidenepyrimidine-2,4,6(1H,3H,5H)-trione and pyrano[2,3-d]-pyrimidine dione derivatives. The products were formed in excellent yields over short reaction times and the catalyst can be reused several times without
Bi-SO3H functionalized ionic liquid based on DABCO as a mild and efficient catalyst for the synthesis of 1,8-dioxo-octahydro-xanthene and 5-arylmethylene-pyrimidine-2,4,6-trione derivatives
1,8-Dioxo-octahydro-xanthenes are easily prepared via the condensation of aldehydes with 1,3-cyclohexadione and/or dimedone using N-sulfonated DABCO as a new and efficient catalyst. This reagent is also efficiently able to catalyze the condensation of aldehydes with barbituric acid leading to 5-arylmethylene-pyrimidine-2,4,6-triones. The structure of the products was characterized by their IR, 1H NMR, and 13C NMR spectroscopy. The present methodology offers several advantages such as ease of preparation and handling of the catalyst, high yields, simple and green procedure, low cost, short reaction times, easy work-up, and preformation of the reaction in the absence of solvent or in water as a green solvent.
Butane-1-sulfonic acid immobilized on magnetic Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub>nanoparticles: A novel and heterogeneous catalyst for the one-pot synthesis of barbituric acid and pyrano[2,3-<i>d</i>] pyrimidine derivatives in aqueous media
reagent was characterized and used for the efficient promotion of the synthesis of barbituric acid and pyrano[2,3‐d] pyrimidine derivatives. All reactions were performed under mild and completely heterogeneous reaction conditions affording products in good to high yields. The catalyst is easily isolated from the reaction mixture by magnetic decantation and can be reused at least eight times without
固定在磁性Fe 3 O 4 @SiO 2纳米粒子(Fe 3 O 4 @SiO 2-磺内酯)上的丁烷-1-磺酸易于通过纳米磁性Fe 3 O 4 @SiO 2的1,4-丁磺酸内酯的直接开环制备。。表征所制备的试剂,并将其用于有效促进巴比妥酸和吡喃并[2,3- d]嘧啶衍生物。所有反应均在温和且完全不均一的反应条件下进行,从而提供高至高收率的产物。通过磁倾析法可以很容易地将催化剂从反应混合物中分离出来,并且可以重复使用至少八次,而不会明显降低活性。
2-Phenyl-2,3-dihydrobenzo[d]thiazole: A Mild, Efficient, and Highly Active in situ Generated Chemoselective Reducing Agent for the One-Pot Synthesis of 5-Monoalkylbarbiturates in Water
作者:Dibakar Deka、Subarna Kalita
DOI:10.1055/s-0036-1591725
日期:2018.3
protocol for the one-pot synthesis of 5-monoalkylbarbiturates from barbituric acids and aldehydes using the in situ generated chemoselectivereducingagent 2-phenyl-2,3-dihydrobenzo[ d ]thiazole from 2-aminothiophenol and benzaldehyde is described. The notable advantages of the protocol are operational simplicity, mild reaction conditions, high yield, short reaction time, and simple workup and purification