One-pot, solvent-free synthesis via Biginelli reaction: Catalyst-free and new recyclable catalysts

First-row transition metal for isocyanide-involving multicomponent reactions (IMCR)

First-row transition metal catalyzed transformations that are able to construct complex molecules from simple, readily obtainable feedstocks have become a keystone of modern synthetic organic chemistry. Particularly, the multicomponent reaction (MCR) involving carbon-carbon (C-C) as well as carbon-heteroatom (C-X) bond formation plays an essential role in many chemical conversions, and insurgencies in these reactions powerfully improve the overall synthetic efficiency. Recently, MCRs emerges rapidly because of its greener sides like eco-friendly nature, swift and straightforward execution, high atom/step economy, and construction of aimed product with lowest or no by-product, usually in quantitative yield. Curiously, the exceptional divalent carbon atoms of isocyanides make them predominantly useful components in multicomponent reactions. As a result of widespread research over the past few decades, numerous well-designed and effective procedures for the first-row TM-catalyzed MCR to afford the various entities have been reported. These aspects are summarized in this review article. A particular focus on comparative discussion of various first-row transition-metal catalyzed isocyanide-based multicomponent reactions through mechanistic details included in the review article.

A nanocrystalline CdS thin film as a heterogeneous, recyclable catalyst for effective synthesis of dihydropyrimidinones and a new class of carbazolyl dihydropyrimidinones via an improved Biginelli protocol

An improved Biginelli protocol for the efficient synthesis of a new class of carbazolyl dihydropyrimidinones mediated by CdS thin film nanoparticles deposited on the inner walls of a glass reactor as a recyclable, heterogeneous catalyst.

Ag₂O on ZrO₂ as a Recyclable Catalyst for Multicomponent Synthesis of Indenopyrimidine Derivatives

We describe the synthesis of silver loaded on zirconia and its use as an efficient catalyst for a one-pot three-component reaction to synthesize 11 indenopyrimidine derivatives, of which 7 are new compounds. The procedure involves substituted benzaldehydes, indane-1,3-dione, and guanidinium hydrochloride, with ethanol as solvent. The proposed green protocol at room temperature is simple and efficient, giving excellent yields (90⁻96%) in short reaction times (<30 min). The protocol works well according to the green chemistry principles with respect to high atom economy, no need for column separation, and reusability of the catalyst, which are attractive features. XRD, TEM, SEM, and BET analysis were used to characterize the catalyst materials.

Green synthesis and corrosion inhibition study of 2-amino-N′-((thiophen-2-yl)methylene)benzohydrazide

2-Amino-N′-((thiophen-2-yl)methylene)benzohydrazide (ATMBH) was synthesized by a conventional method, as well as by microwave (MW) irradiation.