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.
O-Sulfonated poly(4-vinylpyrrolidonium) chloride is prepared from the reaction of poly(4-vinylpyrrolidone) [PVP], as a cheap and commercially available reagent, and neat chlorosulfonic acid at room temperature. A variety of techniques including infrared spectra (IR), thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray diffraction (XRD), pH analysis and Hammett acidity (Ho) were used to characterize this solid acid. This polymeric reagent showed excellent catalytic activity for the synthesis of xanthene derivatives including 1,8-dioxooctahydroxanthenes, 14-aryl-14H-dibenzo[a,j] xanthenes and 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-ones under solvent free conditions. The products were formed in excellent yields over short reaction times and the catalyst can be reused several times without any appreciable loss in its activity.
Succinimide-N-sulfonic acid: An efficient catalyst for the synthesis of xanthene derivatives under solvent-free conditions
作者:Farhad Shirini、Nader Ghaffari Khaligh
DOI:10.1016/j.dyepig.2012.06.022
日期:2012.12
A mild, simple and convenient procedure for the synthesis of xanthene derivatives is described via three component condensation of aldehydes with 2-naphthol, 1,3-cyclohexanedione and/or a mixture of 2-naphthol and 1,3-cyclohexanediones using succinimide-N-sulfonic acid as an efficient, cheap and readily synthesiscatalystundersolvent-freeconditions. The structures of the products were characterized
通过醛与2-萘酚,1,3-环己二酮和/或2-萘酚和1,3-环己二酮的混合物使用琥珀酰亚胺-N进行三组分缩合,描述了一种温和,简单,方便的合成x吨衍生物的方法。-磺酸在无溶剂条件下作为一种高效,廉价且易于合成的催化剂。产品的结构通过其物理常数,与真实样品的比较以及IR,1 H NMR和13 C NMR光谱进行表征。本方法提供了许多优点,例如高收率,简单的方法,低成本,短的反应时间,无溶剂和温和的反应条件以及使用可重复使用的催化剂。
Use of nanoporous Na+-montmorillonite sulfonic acid (SANM) as an eco-benign, efficient and reusable solid acid catalyst for the one-pot synthesis of 14-aryl-14-H-dibenzo[a,j]xanthenes and 1,8-dioxo-dodecahydroxanthene derivatives
作者:Farhad Shirini、Manouchehr Mamaghani、Seyyed Vahid Atghia
DOI:10.1007/s13738-012-0174-4
日期:2013.6
Nanoporous Na+-montmorillonite sulfonic acid was found to be an efficient and green catalyst for the synthesis of various 14-aryl-14H-dibenzo[a,j]xanthenes and 1,8-dioxo-dodecahydroxanthene derivatives by the reaction of aldehydes with 2-naphthol and 1,3-cyclohexanedione, respectively. This novel synthetic method has the advantages of high yields, short reaction times and recyclability of the catalyst, simplicity and easy workup compared to the conventional methods reported in the literature.
Copper iodide nanoparticles on poly(4-vinylpyridine): A new and efficient catalyst for the synthesis of 1,8-dioxooctahydroxanthenes under solvent-free conditions
Poly(4-vinylpyridine)-supported nanoparticles of copper(I) iodide is reported as a new, efficient and recyclable catalyst for the synthesis of 1,8-dioxooctahydroxanthenes under solvent-free conditions. This catalyst can be recovered by simple filtration and recycled up to 10 consecutive runs without losing of its efficiency.