15898-27-8Relevant academic research and scientific papers
Sulfamic acid as efficient and reusable catalytic system for the synthesis of pyrrole, furan, and thiophene derivatives
Luo, Haitang,Kang, Yuru,Li, Qi,Yang, Liming
, p. 144 - 148 (2008)
Sulfamic acid has been utilized for the first time as an efficient and reusable catalytic system for the synthesis of heteroaromatics such as pyrrole, furan, and thiophene derivatives from 1,4-diketones. This new procedure offers significant improvements in the reaction rates and yields in a shorter reaction time and a lower reaction temperature contrasted with the reported results. The recovered catalyst can be reused for subsequent runs with only a gradual decrease in activity. The most important feature is that the reaction process is homogeneous whereas the separation process is heterogeneous, which is often seen in other catalysts, and so it is a good character for technical application.
An approach to the Paal-Knorr pyrroles synthesis catalyzed by Sc(OTf)3 under solvent-free conditions
Chen, Jiuxi,Wu, Huayue,Zheng, Zhiguo,Jin, Can,Zhang, Xingxian,Su, Weike
, p. 5383 - 5387 (2006)
A facile synthesis of N-substituted pyrroles by the Paal-Knorr condensation has been accomplished using a simple procedure. Among different metal triflates screened, 1 mol % Sc(OTf)3 efficiently promoted the reaction to give excellent yield (89-98%) under mild reaction conditions. Additionally, Sc(OTf)3 could be recovered easily after the reactions and reused without evident loss in activity.
Amidosulfonic acid supported on graphitic carbon nitride: novel and straightforward catalyst for Paal–Knorr pyrrole reaction under mild conditions
Azhdari, Asieh,Azizi, Najmedin,Sanaeishoar, Haleh,Tahanpesar, Elham
, p. 625 - 634 (2021)
A novel heterogeneous acidic catalyst was prepared by in situ immobilization of amidosulfonic acid (NH2SO3H) on graphitic carbon nitride (g-C3N4) under hydrothermal conditions. The textural morphology of NH2SO3H/g-C3N4 nanocomposite was characterized via powder X-ray diffraction, FT-IR, TGA, EDX, and scanning electron microscopy. The spatial arrangement of the amidosulfonic acid on the surface of g-C3N4 leads to the construction of a unique solid acid structure, resulting in a substantial enhancement of catalytic activity toward a high efficient preparation of pyrroles by Paal–Knorr reaction. The reactions undergo completion readily with good to excellent yields, with simple purification in an environmentally friendly manner. The NH2SO3H/g-C3N4 nanocomposite can be readily recycled, and no noteworthy reduction in the catalytic activity detected after four runs. Graphic abstract: [Figure not available: see fulltext.]
Facile fabrication of porous magnetic covalent organic frameworks as robust platform for multicomponent reaction
Azizi, Najmedin,Heidarzadeh, Fatemeh,Farzaneh, Fezeh
, (2021/07/26)
The design of cheap yet efficient nanoporous magnetic catalysts for the environmentally benign process's widespread application is an extremely attractive, challenging chemical research field. A novel porous magnetic covalent organic framework was prepared by the condensation reaction of melamine and terephthaladehyde on the surface of 3,4-dihydroxybenzaldehyde coated magnetic Fe3O4 nanoparticles COF@Fe3O4 under hydrothermal conditions for the first time. The high surface area magnetic COF could exhibit superior catalytic activity for sustainable synthesis of trisubstituted and tetrasubstituted imidazoles and pyrroles in good to excellent yields in PEG as solvent under environmentally friendly, ambient conditions and making the overall process economical, efficient, and green. The retrievable catalyst in PEG is general and applicable to a broad substrate scope and functional group compatibility. The structure and morphology of the COF@Fe3O4 were characterized by FTIR, XRD, EDX, and SEM spectroscopy. The COF@Fe3O4 magnetic catalyst was recovered by an external magnet and used for several cycles without significant catalytic activity loss.
Squaric acid catalyzed simple synthesis of N-substituted pyrroles in green reaction media
Azizi, Najmadin,Davoudpour, Anahita,Eskandari, Farshid,Batebi, Ehlham
, p. 405 - 409 (2013/05/09)
An operationally simple and efficient protocol for squaric acid catalyzed synthesis of N-substituted pyrroles via the reaction of 2,5- dimethoxytetrahydrofuran and 2,5-hexandione with aryl amines in green reaction media (water, deep eutectic solvent, and polyethylene glycol) under ultrasound irradiation or thermal conditions in good to excellent yields has been developed.
Microwave assisted synthesis of pyrroles
Danks, Timothy N.
, p. 3957 - 3960 (2007/10/03)
The synthesis of pyrroles by reaction of hexane-2,5-dione with primary amines has been shown to occur in less than 2 minutes under microwave activation.
