201023-86-1

Upstream product

• 108-45-2 m-phenylenediamine 
• 110-13-4 2,5-hexanedione 
• 99-65-0 meta-dinitrobenzene 

Relevant academic research and scientific papers

An expeditious and highly efficient synthesis of substituted pyrroles using a low melting deep eutectic mixture

An expeditious green method for the synthesis of diverse valued substituted pyrroles through a Paal-Knorr condensation reaction, using a variety of amines and 2,5-hexanedione/2,5-dimethoxytetrahydrofuran in the presence of a low melting mixture ofN,N’-dimethylurea andL-(+)-tartaric acid (which acts as a dual catalyst/solvent system), has fruitfully been revealed. Herein, we have disclosed the applicability of this simple yet effective strategy for the generation of mono- and dipyrroles in good to excellent yields. Moreover,C3-symmetric tripyrrolo-truxene derivatives have also been assembled by means of cyclotrimerization, Paal-Knorr and Clauson-Kaas reactions as crucial steps. Interestingly, the melting mixture was recovered and reused with only a gradual decrease in the catalytic activity (over four cycles) without any significant drop in the yield of the product. This particular methodology is simple, rapid, environmental friendly, and high yielding for the generation of a variety of pyrroles. To the best of our knowledge, the present work reveals the fastest greener method reported up to this date for the construction of substituted pyrroles by utilizing the Paal-Knorr synthetic protocol, achieving impressive yields under operationally simple reaction conditions without involving any precarious/dangerous catalysts or unsafe volatile organic solvents.

Synthesis of Fe3O4@L-proline@SO3H as a novel and reusable acidic magnetic nanocatalyst and its application for the synthesis of N-substituted pyrroles at room temperature under ultrasonic irradiation and without solvent

N-Substituted pyrroles have been prepared in high isolated yields (65–90%) by the reaction of hexane-2,5-dione with amines or diamines in the presence of Fe3O4@L-proline@SO3H at ambient temperature under ultrasonic irradiation and without solvent. The experimental procedure involves simple operations, and the products are readily separated by external magnet. The same reaction of hexane-2,5-dione with amines containing electron-acceptor substituents, such as 4-nitroaniline, resulted in fair yields of pyrrole derivatives.

Greener Paal-Knorr Pyrrole Synthesis by Mechanical Activation

A straightforward and solventless synthesis of pyrroles was developed by using mechanochemical activation and a biosourced organic acid as the catalyst. Relative to traditional Paal-Knorr methodologies, various N-substituted pyrroles were obtained in very short reaction times. By reaction with unreactive diketones, desymmetrized aliphatic and aromatic compounds were also synthesized.

Synthesis of two distinct pyrrole moiety-containing arenes from nitroanilines using Paal-Knorr followed by an indium-mediated reaction

Synthesis of arenes substituted with two differently substituted-pyrrole moieties was investigated. A Paal-Knorr condensation reaction of nitroanilines with 1,4-diketone to nitrophenyl-1H-pyrroles followed by an indium-mediated reduction-triggered coupling reaction with another kind of 1,4-diketone resulted in two distinct pyrrole-containing arenes, variously substituted 1-((1H-pyrrol-1-yl)phenyl)-1H-pyrroles, in reasonable yield.

Paal-knorr pyrrole synthesis in water

Water was a suitable medium for Paal-Knorr pyrrole cyclocondensation. Hexa-2,5-dione was reacted with several aliphatic and aromatic primary amines, affording N-substituted 2,5-dimethyl pyrrole derivatives in good to excellent yields. An efficient, green method using water either as environmentally friendly solvent or catalyst was presented.

Sulfamic acid heterogenized on functionalized magnetic Fe3O4 nanoparticles with diaminoglyoxime as a green, efficient and reusable catalyst for one-pot synthesis of substituted pyrroles in aqueous phase

Surface functionalization of magnetic nanoparticles is an elegant way to bridge the gap between heterogeneous and homogeneous catalysis. We have conveniently loaded sulfonic acid groups on amino-functionalized Fe3O4 nanoparticles affording sulfamic acid-functionalized magnetic Fe3O4 nanoparticles (MNPs/DAG-SO3H) as an active and stable magnetically separable acidic nanocatalyst, which was characterized using X-ray diffraction, Fourier transform infrared and energy-dispersive X-ray spectroscopies, scanning and transmission electron microscopies, vibrating sample magnetometry and elemental analysis. The catalytic activity of MNPs/DAG-SO3H was probed through one-pot synthesis of N-substituted pyrroles from γ-diketones and primary amines in aqueous phase at room temperature. The heterogeneous catalyst could be recovered easily by applying an external magnet device and reused many times without significant loss of its catalytic activity.

Nanomagnetically modified sulfuric acid (γ-Fe2O 3@SiO2-OSO3H): An efficient, fast, and reusable catalyst for greener Paal-Knorr pyrrole synthesis

Paal-Knorr pyrrole synthesis was performed in the presence of superparamagnetic nanoparticles of modified sulfuric acid (γ-Fe 2O3@SiO2-OSO3H) as an efficient and magnetically separable catalyst. Recovery of the catalyst was simple using a magnet, allowing its reuse without significant loss of its catalytic activity (over five cycles).

One-pot tandem reactions for direct conversion of thiols and disulfides to sulfonic esters, and Paal-Knorr synthesis of pyrrole derivatives catalyzed by TCCA

A convenient synthesis of sulfonic esters from thiols and disulfides is described. In situ preparation of sulfonyl chlorides from thiols is accomplished by oxidation with trichloroisocyanuric acid (TCCA), tetra-butylammonium chloride (t-Bu4NCl), and water. The sulfonyl chlorides are then further allowed to react with phenol derivatives in the same reaction vessel. Also, a facile synthesis of N-substituted pyrroles by the reaction of hexane-2,5-dione with primary amines has been accomplished using TCCA as a catalyst under mild condition with excellent yields.

An efficient and green procedure for synthesis of pyrrole derivatives by Paal-Knorr condensation using sodium dodecyl sulfate in aqueous micellar

A simple, economical, and green approach to the synthesis of N-substituted pyrroles using sodium dodecyl sulfate as surfactant in water is described. The experiment protocol features simple operations, and the products are isolated in high to excellent yields (60-98%).

Silica sulfuric acid (SSA) as a solid acid heterogeneous catalyst for one-pot synthesis of substituted pyrroles under solvent-free conditions at room temperature

A variety of N-substituted pyrroles have been synthesized by reacting γ-diketones with amines, diamines or triamine in the presence of silica sulfuric acid (SSA) at room temperature under solvent-free conditions. The experiment protocol features simple operations, and the products are isolated in high to excellent yields (70-98%).