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

Exploring the synthetic potential of a g-C3N4·SO3H ionic liquid catalyst for one-pot synthesis of 1,1-dihomoarylmethane scaffolds via Knoevenagel-Michael reaction

A highly promising approach for the synthesis of functionalized 1,1-dihomoarylmethane scaffolds (bis-dimedones, bis-cyclohexanediones, bis-pyrazoles, and bis-coumarins) using g-C₃N₄·SO₃H ionic liquid via Knoevenagel-Michael reaction has been developed and the synthesized derivatives were well characterized using spectral studies. The method involved the reaction of C-H activated acids with a range of aromatic aldehydes, in a 2 : 1 ratio catalyzed by a g-C₃N₄·SO₃H ionic liquid catalyst. The use of g-C₃N₄·SO₃H as a catalyst has several benefits, such as low cost, easy preparation, and high stability. It was synthesized from urea powder and chloro-sulfonic acid and was thoroughly characterized using FT-IR, XRD, SEM, and HRTEM. The present work unveils a promising and environmentally friendly method for synthesizing 1,1-dihomoarylmethane scaffolds with high yield, selectivity, and efficiency, using mild reaction conditions, no need for chromatographic separation, and short reaction times. The approach adheres to green chemistry principles and offers a viable alternative to the previously reported methods.

Recent Developments on Five-Component Reactions

Multicomponent reactions (MCRs) have inherent advantages in pot, atom, and step economy (PASE). This important green synthetic approach has gained increasing attention due to high efficiency, minimal waste, saving resources, and straightforward procedures. Presented in this review article are the recent development on 5-compoment reactions (5CRs) of the following six types: (I) five different molecules A + B + C + D + E; pseudo-5CRs including (II) 2A + B + C + D, (III) 2A + 2B + C, (IV) 3A + B + C, (V) 3A + 2B, and (VI) 4A + B. 5CRs with more than five-reaction centers are also included.