An unexpected multi-component reaction to synthesis of 3-(5-amino-3-methyl-1H-pyrazol-4-yl)-3-arylpropanoic acids in ionic liquid

Design, preparation and application of the semicarbazide-pyridoyl-sulfonic acid-based nanocatalyst for the synthesis of pyranopyrazoles

A novel, efficient, and recoverable nanomagnetic catalyst bearing the semicarbazide linkers, namely, Fe₃O₄@SiO₂@OSi(CH₂)₃-N(3-pyridoyl sulfonic acid)semicarbazide (FSiPSS) was designed, synthesized and characterized by the use of various techniques such as FT-IR, EDX, elemental mapping analysis, XRD, SEM, TEM, TGA/DTA, BET, and VSM. Then, the catalytic capability of the novel prepared nanomagnetic FSiPSS catalyst was successfully investigated in the synthesis of diverse pyranopyrazoles through a one-pot four-component condensation reaction of ethyl acetoacetate, hydrazine hydrate, aromatic aldehydes, and malononitrile or ethyl cyano-acetate by the help of ultrasonication in very short reaction time, good to high yields and easy work-up (Fig. 1). Figure 1 Synthesis of diverse pyranopyrazoles by the FSiPSS nano-catalyst.

Synthesis of a novel category of pseudo-peptides using an Ugi three-component reaction of levulinic acid as bifunctional substrate, amines, and amino acid-based isocyanides

The synthesis of a novel category of pseudo-peptides via intramolecular Ugi reaction of levulinic acid (4-oxopentanoic acid), aromatic and aliphatic amines, and amino acid-based isocyanides is reported. Levulinic acid was applied as a bifunctional substrate containing both carbonyl and acid moieties suitable for the Ugi reaction. This article provides a facile and convenient one-pot procedure for the synthesis of peptide-like heterocyclic molecules containing 2-pyrrolidone (γ-lactam), amide and ester functional groups with good to excellent yields.

An Efficient Three-Component Synthesis of Trispiropyrrolidines Derivatives through 1,3-Dipolar Cycloaddition Reaction

The synthesis of novel trispiropyrrolidine derivatives has been achieved by a one-pot, three-component 1,3-dipolar cycloaddition reaction of 3-aryl-5-arylmethylenespiro[indole-3’,2-[1,3]thiazolane]-2'(1 H),4-dione, isatin and sarcosine in refluxing toluene which produced the corresponding cycloadducts in good yields. The structures were determined by 1H NMR, IR and elementary analysis.

A facile one-pot ultrasound assisted for an efficient synthesis of 1H-spiro[furo[3,4-b]pyridine-4,3'-indoline]-3-carbonitriles

A convenient one-pot protocol was developed for the synthesis of 1H-spiro[furo[3,4-b]pyridine-4,3'-indoline]-3-carbonitrile derivatives. This reaction was carried out through a three component condensation reaction of isatins, malononitrile, and anilinolactones in the presence of a catalytic amount of Et3N as an inexpensive and available basic catalyst in THF under ultrasound irradiation. The products were obtained in high yields and short reaction times. The main advantage of this synthetic method is that the obtained products in ultrasonic irradiations are different from classical heating.