3-甲基-1-磺酸咪唑鎓硫酸氢存在下四组分一锅法合成苯并[g]茚并[2,1-b]喹啉衍生物(英文)

A simple and facile synthesis of 12-arylbenzo[g]indeno[2,1-b]quinoline-6,11,13-trione deriv-atives was accomplished by the one-pot condensation of 2-hydroxynaphthalene-1,4-dione, aryl aldehydes, 2H-indene-1,3-dione, and ammonium acetate under solvent-free conditions in the presence of a Brnsted ionic liquid catalyst, namely 3-methyl-1-sulfonic acid imidazolium hydrogen sulfate.     

Poly(4-vinylpyridinium)hydrogen sulfate: a novel and efficient catalyst for the synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes under conventional heating and ultrasound irradiation

A simple and convenient procedure for the synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes is described through a one-pot condensation of 2-naphthol with aryl aldehydes in the presence of poly(4-vinylpyridinium)hydrogen sulfate as an efficient, cheap, readily synthesized and eco-friendly catalyst in a solvent free media using conventional heating and ultrasound irradiation.     

Green one-pot multicomponent synthesis of pyrrolidinones using planetary ball milling process under solvent-free conditions

This paper presents a novel and efficient protocol for the synthesis of pyrrolidinones using catalytic loading of 1,1'-butylenebis(3-sulfo-3H-imidazol-1-ium) hydrogen sulfate as a recyclable Brönsted acid ionic liquid through ball milling process at room temperature under solvent-free conditions. The developed method provides good to excellent yields of various pyrrolidinones in environmentally friendly conditions. Furthermore, this efficient protocol displays a combination of the synthetic advantage of one-pot multicomponent reaction with ecological benefits and convenience of a mechanochemical procedure.     

聚乙烯基吡啶高氯酸盐作为高效固体酸催化剂在无溶剂条件下催化醛化学选择性制备二乙酸盐简

Poly(4-vinylpyridinium) perchlorate has been used as a supported, recyclable, environmentally-benign catalyst for the formation of acylals from aliphatic and aromatic aldehydes in good to excellent yields under solvent-free conditions. Notably, the reaction conditions were tolerant of ketones. This methodology offers several distinct advantages, including its operational simplicity and high product yield, as well as being green in terms of avoiding the use of toxic catalysts and solvents. Furthermore, the catalyst can be recovered and reused several times without any loss in its activity.     

N-磺酸基聚(4-乙烯吡啶)硫酸氢铵作为新型、高效、可重复使用的固体酸催化剂用于无溶剂条件下酰化反应(英文)

N-Sulfonic acid poly(4-vinylpyridinum) hydrogen sulfate has been developed as a recyclable solid acid catalyst for the acetylation of alcohols, phenols, thiols, and amines, as well as the 1,1- diacetylation of aldehydes under solvent-free conditions at room temperature. The acetylated products were formed in good to excellent yields over short reaction times, and the catalyst could be readily recovered by filtration and used several times without any discernible loss in activity. The hydrogen sulfate anion of the catalytic system was found to play a critical role in enhancing the reaction time and yield of the acetylation reaction.     

Poly(4-vinylpyridinium) hydrogensulfate catalyzed synthesis of 12-aryl-12H-indeno[1,2-b]naphtho[3,2-e]pyran-5,11,13-triones

A simple and facile synthesis of 12-aryl-12H-indeno[1,2-b]naphtho[3,2-e]pyran-5,11,13-trione derivatives was accomplished via the one-pot condensation of 2-hydroxynaphthalene-1,4-dione, aldehydes, and 2H-indene-1,3-dione at 100 °C under solvent-free conditions in the presence of the solid acid catalyst, poly(4-vinylpyridinium) hydrogensulfate. This method has the advantages of high yields, clean reactions, simple methodology, and short reaction times. The catalyst could be recycled and reused four times without significant loss of activity. The structures of the novel compounds were confirmed by IR, ¹H NMR, and elemental analysis.     

N-sulfonic acid poly(4-vinylpyridinium) chloride: an efficient and reusable solid acid catalyst in N-Boc protection of amines

N-sulfonic acid poly(4-vinylpyridinium) chloride is easily prepared by the reaction of poly(4-vinylpyridine) with neat chlorosulfonic acid. This reagent can be used as an efficient catalyst for the N-Boc protection of amines at room temperature and neat conditions. This new method consistently has the advantages of excellent yields and short reaction times. Further, the catalyst can be reused and recovered for several times.     

Ultrasound-assisted one-pot synthesis of substituted coumarins catalyzed by poly(4-vinylpyridinium) hydrogen sulfate as an efficient and reusable solid acid catalyst

Poly(4-vinylpyridinium) hydrogen sulfate solid acid was found to be efficient catalyst for synthesis of substituted coumarins via Pechmann reaction using ultrasound irradiation at room temperature and neat condition in high yields with short reaction times. This methodology offers momentous improvements over various options for the synthesis of coumarins with regard to yield of products, simplicity in operation and green aspects by avoiding toxic catalysts and solvents. Further, the catalyst can be reused and recovered for several times.     

Greener and practical synthesis of 4,4′-(arylmethylene)bis(3-methyl-1-phenyl-1H-pyrazol-5-ol)s through a conventional heating and a mechanochemical procedure

A new catalytic application of 4,4′-trimethylenedipiperidine for the efficient synthesis of 4,4′-(arylmethylene)bis(3-methyl-1-phenyl-1H-pyrazol-5-ol)s is developed. According to the principles of green chemistry, the reaction was performed by conventional and non-conventional processes: (a) in the refluxing ethanol using a catalytic amount of organocatalyst; (b) at room temperature in the presence of organocatalyst in a planetary ball mill under solvent-free conditions. The organocatalyst could be reused up to 10 runs, and a negligible reduction of catalytic activity was detected. A variety of substituted 4,4′-(arylmethylene)bis(3-methyl-1-phenyl-1H-pyrazol-5-ol)s were obtained in good–to-excellent yields under eco-friendly conditions. 4,4′-Trimethylenedipiperidine is commercially available and easy to handle and storage, less toxic, non-flammable, as well as it shows high thermal stability and good solubility in water. The current methodology has merits including (a) wide substrate-scope and high yields of the desired products in the short reaction times, (b) avoiding the use of hazardous solvents and acidic and metal-containing catalysts, (c) minimize the generation of hazardous waste, and (d) simple workup process. Based on great potential as a promising organocatalyst, we hope it can be used as a greener alternative to piperidine for other organic transformations.