Palladium/Copper-Catalyzed Oxidative Arylation of Terminal Alkenes with Aroyl Hydrazides

Visible-Light Induced Radical Addition-Elimination Reaction for Constructing Allylic Sulfones from Sulfonyl Chlorides and Allyl Bromides

Allyl sulfones are commonly present in bioactive compounds and organic building blocks. This work introduces a photocatalytic radical addition-elimination reaction involving readily accessible sulfonyl chlorides and allyl bromides. It delivers structurally diverse allylic sulfones in moderate to excellent yields, showcasing a high tolerance to functional groups. Notably, this method operates under mild reaction conditions without the need for oxidants, stoichiometric reducing metals, or additives.

Different Schiff Bases-Structure, Importance and Classification

Schiff bases are a vast group of compounds characterized by the presence of a double bond linking carbon and nitrogen atoms, the versatility of which is generated in the many ways to combine a variety of alkyl or aryl substituents. Compounds of this type are both found in nature and synthesized in the laboratory. For years, Schiff bases have been greatly inspiring to many chemists and biochemists. In this article, we attempt to present a new take on this group of compounds, underlining of the importance of various types of Schiff bases. Among the different types of compounds that can be classified as Schiff bases, we chose hydrazides, dihydrazides, hydrazones and mixed derivatives such as hydrazide-hydrazones. For these compounds, we presented the elements of their structure that allow them to be classified as Schiff bases. While hydrazones are typical examples of Schiff bases, including hydrazides among them may be surprising for some. In their case, this is possible due to the amide-iminol tautomerism. The carbon-nitrogen double bond present in the iminol tautomer is a typical element found in Schiff bases. In addition to the characteristics of the structure of these selected derivatives, and sometimes their classification, we presented selected literature items which, in our opinion, represent their importance in various fields well.

Facile C-N Bond Cleavage of Primary Aliphatic Amines by (Salen)ruthenium(VI) Nitrido Complexes

We report the first example of oxidative cleavage of the strong C-N bonds of primary amines by a ruthenium(VI) nitrido complex. The driving force for this very fast C-N cleavage...

Amine-Directed Mizoroki-Heck Arylation of Free Allylamines

The transition metal-catalyzed Mizoroki−Heck reaction is a powerful method to synthesize C–C bonds, allowing access to several important pharmaceuticals. Traditionally free amines have not been compatible with these approaches due...

The Synthesis and Evaluation of Amidoximes as Cytotoxic Agents on Model Bacterial E. coli Strains

The biological research on newly synthesized amidoximes, Boc-protected amidoximes and Boc-derived amidines, obtained by a reduction of the parent amidoximes is reported, herein. Due to the presence of a free amino group in both amidines and amidoximes, these compounds can undergo various chemical reactions such as N-alkylation and N-acylation. One such reaction is Boc-protection, often used in organic synthesis to protect the amino and imino groups. Until now, Boc-protected amidoximes have not been tested for biological activity. Amidoxime derivatives were tested on bacterial E. coli strains. Initial cellular studies tests and digestion with Fpg after the modification of bacterial DNA, suggest that these compounds may have greater potential as antibacterial agents compared to antibiotics such as ciprofloxacin (ci), bleomycin (b) and cloxacillin (cl). The described compounds are highly specific for pathogenic E. coli strains on the basis of the model strains used and may be used in the future as new substitutes for commonly used antibiotics in clinical and hospital infections in the pandemic era.

Cu-Catalyzed Oxidative Thioesterification of Aroylhydrazides with Disulfides

An alternative thioesterification reaction via copper-catalyzed oxidative coupling of readily available aroylhydrazides with disulfides is developed, in which oxidative expulsion of N₂ overcomes the activation barrier between the carboxylic acid derivatives and the products. The reaction produces various thioesters in good to excellent yields with good functional group tolerance. In the reaction, stable and easily available aroylhydrazides are used as acyl sources and the relatively odorless disulfides are used as S sources. Mechanistic investigations demonstrate that the reaction of copper salt and oxidant (NH₄)₂S₂O₈ allows for achievement of tandem processes, including deprotonation, free-radical-mediated denitrogenation, and C-S bond formation.

Palladium/copper-catalyzed arylation of alkenes with N′-acyl arylhydrazines

An efficient and ligand-free palladium/copper-catalyzed Heck-type coupling reaction of N′-acyl arylhydrazines with olefins for the practical synthesis of arylalkenes.

Open-air oxidative Mizoroki–Heck reaction of arylsulfonyl hydrazides with alkenes

A palladium(ii)-catalyzed oxidative Mizoroki–Heck reaction of arylsulfonyl hydrazides with alkenes was developed employing Pd(OAc)₂ and pyridine ligand L9 as a catalyst system and ​atmospheric air as the sole oxidant in an open-vessel manner.

Electron transfer-induced coupling of haloarenes to styrenes and 1,1-diphenylethenes triggered by diketopiperazines and Potassium tert-butoxide

The coupling of haloarenes to styrenes and 1,1-diarylethenes has been achieved with potassium tert-butoxide in the presence of N,N'-dialkyldiketopiperazines. In contrast to previously reported reactions where phenanthroline has been used to mediate the reactions, the use of diketopiperazines can lead to either 1,1,2-triarylethenes or 1,1,2-triarylethanes, depending on the conditions used.

Rhodium-catalyzed oxidative decarbonylative Heck-type coupling of aromatic aldehydes with terminal alkenes

A rhodium-catalyzed oxidative decarbonylative Heck-type coupling of aromatic aldehydes and terminal alkenes to afford 1,2-disubstituted alkenes with good regio- and E-selectivity is developed.

Kinetic resolution of primary allylic amines via palladium-catalyzed asymmetric allylic alkylation of malononitriles

A new strategy has been developed for the catalytic kinetic resolution of primary allylic amines via enantioselective C–N bond cleavage.