N-Arylimidazole synthesis by cross-cycloaddition of isocyanides using a novel catalytic system

C-H functionalization enabled by multiple isocyanides

Past decades have witnessed significant advance of isocyanides as a class of versatile organic synthons as well as their broad applications in multi-component reactions (MCRs) and other tandem reactions. Reactions involving multiple isocyanides allow the construction of molecules with further diversification and complexity, while C-H functionalization emphasizes the advantages of high atom economy, broad substrate availability and great synthetic efficiency. This promising synergistic strategy of C-H functionalization involving multiple isocyanides provides a variety of valuable synthetic methods for organic chemists' toolbox and offers considerable potential in pharmaceutical chemistry and materials science as well. The present review outlines in detail various reaction types of C-H functionalization enabled by multiple isocyanides, and the relevant mechanistic rationale is discussed.

Decarboxylative N-Formylation of Amines with Glyoxylic Acid Promoted by H2O2

A novel method for the synthesis of formamides through the decarboxylative N-formylation of amines with glyoxylic acid has been developed. This transformation provides an efficient protocol for the synthesis of various formamides with moderate to excellent yields, and it can accommodate a wide range of functional groups under metal free and base free conditions. In addition, the large-scale experiments and high chemoselectivity have shown great potential application of this strategy.

Synthesis, crystal structure, Hirshfeld surface analysis, DFT, molecular docking and molecular dynamic simulation studies of (E)-2,6-bis(4-chlorophenyl)-3-methyl-4-(2-(2,4,6-trichlorophenyl)hydrazono)piperidine derivatives

A novel drug to treat SARS-CoV-2 infections and hydroxyl chloroquine analogue, (E)-2,6-bis(4-chlorophenyl)-3-methyl-4-(2-(2,4,6-trichlorophenyl)hydrazono)piperidine (BCMTP) compound has been synthesized in one pot reaction. The novel compound BCMTP has been characterized by FT-IR, ¹H-NMR, ¹³C-NMR and single-crystal X-ray diffraction patterns. Crystal packing is stabilized by C8-H8A•••Cl10ⁱ, C41-H41•••Cl1ⁱⁱ and N1-H1A•••Cl6ⁱⁱⁱ intermolecular hydrogen bonds. From the geometrical parameters, it is observed that the piperidine ring adopts chair conformation. Hirshfeld surface analysis was carried out to quantify the interactions and an interaction energy analysis was done to study the interactions between pairs of molecules. The geometrical structure was optimized by density functional theory (DFT) method at B3LYP/6-31G (d, p) as the basic set. The smaller binding energy value provides the higher reactivity of BCMTP compound than hydroxyl chloroquine and was corrected by high electrophilic and low nucleophilic reactions. The stability and charge delocalization of the molecule were also considered by natural bond orbital (NBO) analysis. The HOMO-LUMO energies describe the charge transfer which takes place within the molecule. Molecular electrostatic potential has also been analysed. Molecular docking studies are implemented to analyse the binding energy of the BCMTP compound against standard drugs such as the crystal structure of ADP ribose phosphatase of NSP3 from SARS-CoV-2 in complex with MES and SARS-CoV-2 main protease with an unliganded active site (2019-nCoV, corona virus disease 2019, COVID-19) and found to be considered having better antiviral agents. Molecular dynamics simulation was performed for COVID-19 main protease (Mpro: 6WCF/6Y84) to understand the elements governing the inhibitory effect and the stability of interaction under dynamic conditions.

N-Formylsaccharin: A Sweet(able) Formylating Agent in Mechanochemistry

The acylation of amines has always attracted a deep interest as a synthetic route due to its high versatility in organic chemistry and biochemical processes. The purpose of this article is to present a mechanochemical acylation procedure based on the use of acyl-saccharin derivatives, namely N-formylsaccharin, N-acetylsaccharin, and N-propionylsaccharin. This protocol furnishes a valuable solvent-free alternative to the existing processes and aims to be highly beneficial in multi-step procedures due to its rapid and user-friendly workup.

Formamidation of a wide range of substituted and functionalized amines with CO and a base

We have developed a base mediated formamidation of amines with CO under mild conditions, which allows for the synthesis of a wide range of aromatic and aliphatic formamides in high yields and gram amounts in the absence of a transition metal.

Rhodium-catalyzed homodimerization–cyclization reaction of two vinyl isocyanides: a general route to 2-(isoquinolin-1-yl)oxazoles

A novel rhodium-catalyzed homodimerization–cyclization reaction of two vinyl isocyanides has been developed for the synthesis of 2-(isoquinolin-1-yl)oxazoles by formation of three new bonds and two rings in a single step.

A formal (5+1) annulation reaction from heterodimerization of two different isocyanides: stereoselective synthesis of 2H-benzo[b][1,4]oxazin-2-one

A novel (5+1) annulation reaction of functionalized 2-isocyanophenyloxyacrylate and aromatic, aliphatic isocyanides has been disclosed. This strategy allows for a quick access to many 2H-benzo[b][1,4]oxazin-2-one derivatives.

Catalytic Isonitrile Insertions and Condensations Initiated by RNC-X Complexation

Isonitriles are delicately poised chemical entities capable of being coaxed to react as nucleophiles or electrophiles. Directing this tunable reactivity with metal and non-metal catalysts provides rapid access to a large array of complex nitrogenous structures ideally functionalized for medicinal applications. Isonitrile insertion into transition metal complexes has featured in numerous synthetic and mechanistic studies, leading to rapid deployment of isonitriles in numerous catalytic processes, including multicomponent reactions (MCR). Covering the literature from 1990-2014, the present review collates reaction types to highlight reactivity trends and allow catalyst comparison.