Abstract We have focused our attention on cycloisomerization reactions involving silver‐ and gold‐based homogeneous catalysis. This topic is divided into two parts: one relating to with an allene group the other alkyne group. In each case we then studied different partners such as carbonyl/carboxy groups, imines, amides or alkenes. Reactions systems are also briefly reported, along miscellaneous transformations. Our purpose stimulate some discussion by setting together contributions of...

Abstract An efficient and versatile tandem process of acetalization cycloisomerization reactions has been developed for the 1‐alkynyl‐2‐carbonylquinoline substrates. The reaction occurs thanks to Au I Ag catalysis. Silver(I) catalysis extensively studied (11 different silver species) on a broad range quinoline derivatives (variation alkyne substituent, carbonyl function nucleophiles), leading variety furoquinoline pyranoquinoline moieties. insight is given presumed mechanism along with...

We report the synthesis of various phthalazines

A Ag-catalyzed versatile and efficient access to 1H,1-arylisochromenes is reported. Starting from ortho-alkynylbenzaldehydes bearing various substitution patterns on the benzaldehyde alkynyl units, use of silver triflate (10 mol %) allowed a domino hydroarylation/cycloisomerization reaction process, leading aryl-functionalized 1H-isochromene (>10 compounds, 80–98% yields). Notably, conditions were also compatible with benzaldehydes an aliphatic-substituted moiety modest good yields (34–88%,...

Carbon–carbon bond formation reactions are of longstanding interest in organic chemistry. Improvements the methods targeting its creation still being performed, especially thanks to development innovative methodologies transition metal catalysis and photocatalysis. This review will tackle combination photoredox cycles create carbon–carbon bonds, focusing on four metals most reported literature this domain: Ni, Pd, Au Cu.

Abstract The synthesis and characterization of original NHC ligands based on an imidazo[1,5‐ a ]pyridin‐3‐ylidene (IPy) scaffold functionalized with flanking barbituric heterocycle is described as well their use tunable for efficient gold‐catalyzed C−N, C−O, C−C bond formations. High activity, regio‐, chemo‐, stereoselectivities are obtained hydroelementation domino processes, underlining the excellent performance (TONs TOFs) these IPy‐based in gold catalysis. reactions 1,6‐enynes give rise...

A silver-catalyzed cycloisomerization reaction of a series o-alkynylbenzohydroxamic acids is reported. Several 5-exo-dig and 6-endo-dig modes cyclization were observed with the nitrogen or oxygen atoms amide group acting as nucleophiles. The selectivity was strongly dependent on silver salt used presence triphenylphosphine an additive. Indeed, while use Ag2O at room temperature allowed isolation isobenzofuran-1-one oximes (7 compounds, 48–92% yield), [Ag(Im)]n concomitant addition 2 equiv...

Accessibility of highly functionalized polyheterocyclic compounds with efficient catalytic methods represents a long-standing challenge for organic chemists. The use transition metal catalysts and the recent development gold(III) complexes opens new opportunities. We herein report straightforward gold(III)-catalyzed domino cyclization / functionalization reactions to access scaffolds biological interest. methodology developed here is applied synthesis isochromenes through...

Background: The acridine scaffold is of interest since its DNA affinity and intercalative properties make it an important pharmacophore for the design antitumor drugs targeting DNA. global substitution on heterocycle crucial a specific biological activity also selectivity tumor cells. Objective: Our aim to review most promising therapeutic developments within vast research field dealing with derivatives by pinpointing new trends directions. Methods: patent search covered 2000 – 2008 period...

The use of a powerful aminobenzannulation reaction has been applied for the synthesis amino-substituted quinolines, dibenzofurans, and carbazoles. precursors are heterocycles bearing methyl ketone group ortho to an internal alkyne. They commercially available or can be obtained in three four classical efficient reactions: Vilsmeier-Haack, Sonogashira (diversity point), Grignard, Ley's oxidation. Upon reaction-classical conditions being pyrrolidine neat solvent 4 A MS-an interesting range...

Carbon–heteroatom bond formation is a long‐standing hot topic in organic chemistry owing to the ubiquitous presence of these bonds molecules. A major pathway form them heterofunctionalization unsaturated moieties mediated by transition metals or radical initiators. Recently, visible‐light catalysis has become powerful method for synthesis many chemical bonds, and carbon–heteroatom attracted particular attention photochemists. In this review, we highlight recent advances photocatalysis C–N,...

Visible light catalysis allows the regioselective synthesis of oxazolines in high yields. The mild photosensitized manifold leverages intermolecular formation with a wide functional group tolerance on both benzoyl azides and alkenes partners. Mechanistic investigations suggest sensitization azide moiety as key activation step.

Research on synthesizing nitrogen-containing heterocyclic scaffolds is important because these structures are commonly found in Nature, such as the alkaloids' family. In our study, we propose a new method to synthesize isoquinoline core using an electron donor-acceptor (EDA) complex strategy. Our mechanistic investigations have confirmed that synthesis process operates through EDA mechanism, which not extensively discussed literature, particularly regarding its applications alkynyl...

Silver-catalyzed tandem acetalization and cycloisomerization reactions were found to lead various furoquinolines, a nitrogen effect was noticed for AgOTf reactivity, since the cyclization mode switched from 6-endo-dig 5-exo-dig; these observations silver imidazolate polymer is proposed as stable catalyst.

Cationic lipids are at present very actively investigated for gene transfer studies and therapy applications. Basically, they rely on the formation of DNA/lipid aggregates via electrostatic interactions between their cationic headgroup negatively charged DNA. Although structure/activity relationships not well understood, it is generally agreed that nature positive impacts transfection activity. Thus, we have directed our efforts toward development with novel moieties. In work, explored...

[reaction: see text] A new aminobenzannulation methodology has been developed and applied successfully to the synthesis of 1-amino-acridines. The key last step goes through an enamine intermediate that was detected in some cases. When pyrrolidine powdered 4 molecular sieves were used, took place subsequently, whereas for other secondary amines, neutral Al(2)O(3) or PtCl(2) catalysis necessary.

A mild and general method for the direct alkynylation of azoles such as pyrrole, indole, 7-azaindole is described here. Using a simple catalytic system Pd(OAc)2 (2.5 mol %), P(tBu)2Me·HBF4 (5 NaOAc (2 equiv) allowed regioselective introduction various alkynyl residues at C-2 position pyrroles. Interestingly, was also observed on C-3-substituted indoles, whereas classical C-3 obtained selected unsubstituted indoles 7-azaindole. Our methodology has been illustrated by efficient synthesis...

In this review we chose to concentrate on the bibliography data from 2013 2015 (until February), related application of Inverse Electron Demand Diels-Alder (IEDDA) reaction synthesis heterocycles, as building blocks for natural products synthesis. Moreover, IEDDA recently developed bioorthogonal ligations (in 2008), using tetrazines moieties diene partners, and engineered alkenes or alkynes dienophiles, will be detailed. The in vivo applications are particularly amazing undoubtedly...

Abstract Cationic lipids are currently actively investigated as an alternative approach to recombinant viruses for gene transfer studies and therapy applications. Basically, they rely on the formation of lipid/DNA aggregates via electrostatic interactions between their cationic headgroup negatively charged DNA. The development new amphiphilic structures should allow shed light still poorly understood structure/activity relationship thereby help design improved vectors. It appears that...