10266-18-9

Upstream product

• 369-57-3 benzenediazonium tetrafluoroborate 
• 501-65-5 diphenyl acetylene 
• 75-05-8 acetonitrile 
• 62-53-3 aniline 
• 10341-75-0 (E)-1-phenylethanone oxime 
• 103-84-4 Acetanilid 
• 103-79-7 1-phenyl-acetone 
• 2835-77-0 (2-aminophenyl)(phenyl)methanone 

Downstream Products

• 119225-93-3 2-(3,4-diphenylquinolyliden-2-yl)-1-phenylethanone 

Relevant academic research and scientific papers

Synthesis of Quinolines through Three-Component Cascade Annulation of Aryl Diazonium Salts, Nitriles, and Alkynes

An efficient and rapid synthesis of multiply substituted quinolines is described. This method is enabled by a three-component cascade annulation of readily available aryl diazonium salts, nitriles, and alkynes. This reaction is catalyst- and additive-free. Various aryl diazonium salts, nitriles, and alkynes can participate in this transformation, and the yields are up to 83%.

Weakly Coordinated Cobaltacycles: Trapping Catalytically Competent Intermediates in Cp*CoIII Catalysis

Herein, we disclose the synthesis of metallacyclic Cp*CoIII complexes containing weakly chelating functional groups. We have employed these compounds not only as an exceptional platform for accessing some of the most widely invoked transient intermediates in C?H functionalization processes but also as competent catalysts in different Cp*Co-catalyzed transformations, including a benchmark coupling reaction.

A Tf2O-Promoted Synthesis of Functionalized Quinolines from Ketoximes and Alkynes

A new general synthesis of quinolines was developed from ketoximes and alkynes in the presence of Tf2O. It offered the first direct synthesis of quinolines by using the nitrilium salts generated in situ from a Tf2O-promoted Beckmann rearrangement of ketoximes under very easy conditions. (Figure presented.).

Metal-Free One-Pot Synthesis of (Tetrahydro)Quinolines through Three-Component Assembly of Arenediazonium Salts, Nitriles, and Styrenes

A highly efficient and convenient metal-free, one-pot synthesis of diversely substituted (tetrahydro)quinolines has been achieved through a three-component assembly reaction of arenediazonium salts, nitriles, and styrenes. In sharp contrast to the prior works with the same reagent blend, the formation of N-arylnitrilium intermediates from arenediazonium salts and nitriles was followed by reaction with styrenes, leading to 3,4-dihydroquinolinium salts as a common intermediate. These could be further transformed to quinolines and tetrahydroquinolines depending on the reaction conditions. The advantages of this protocol include its simplicity, metal-free and mild conditions, readily available starting materials, and good functional group tolerance. (Figure presented.).

Cascade annulations of aryldiazonium salts, nitriles and halo-alkynes leading to 3-haloquinolines

A regiospecific access to 3-haloquinolines has been developed via a three-component annulation of aryldiazonium salts, nitriles and haloalkynes. This reaction proceeds through an initial formation of reactive nitrilium ion and further cascade annulation with haloalkynes. This method provides a straightforward access to a diverse array of functionalized quinolones (28 examples) under mild conditions and exhibits broad functional group tolerance. Applications of this method in a gram scale reaction and a formal synthesis of Pitavastatin are illustrated.

Synthesis of Functionalized Quinolines through a Reaction of Amides and Alkynes Promoted by Triflic Anhydride/Pyridine

A concise, novel and flexible metal-free single step to synthesize functionalized quinolines is reported. Triflic anhydride-mediated (Tf2O) activation of amides is discussed in the presence of pyridine to offer strong electrophiles, thereby showcasing excellent productivity, high regio- and chemoselectivity, and widely tolerable substrates. This approach provides a straightforward and efficient way to construct azaheterocycle structures.

Indole Synthesis via Cobalt(III)-Catalyzed Oxidative Coupling of N-Arylureas and Internal Alkynes

A mild Co(III)-catalyzed oxidative annulation of N-arylureas and internal alkynes has been developed. The use of less electrophilic ureas other than acetamides as directing groups is crucial for the reaction. A broad range of synthetically useful functional groups are compatible with this reaction, thus providing a new opportunity for the synthesis of diverse indoles.

Redox-Neutral Couplings between Amides and Alkynes via Cobalt(III)-Catalyzed C-H Activation

C-H activation assisted by a bifunctional directing group has allowed the construction of heterocycles. This is ideally catalyzed by earth-abundant and eco-friendly transition metals. We report Co(III)-catalyzed redox-neutral coupling between arenes and alkynes using an NH amide as an electrophilic directing group. The redox-neutral C-H activation/coupling afforded quinolines with water as the sole byproduct.

Control over Organometallic Intermediate Enables Cp?Co(III) Catalyzed Switchable Cyclization to Quinolines and Indoles

Achieving controllable C-H functionalization to elaborate valuable compounds from simple chemicals is attractive and highly desirable, especially if nonprecious transition metal catalysts can be used. However, controlling selectivity in these transformations remains a continuous challenge to synthetic chemists. Herein, we show for the first time that control over the reactive organometallic intermediate enables the switchable synthesis of quinoline and indole from amides and alkynes through C-H activation using Cp?Co(III). The keys to this strategy are (1) introducing a Lewis acid to greatly accelerate the dehydrative cyclization, which can outcompete dehydrogenative cyclization, and (2) tuning the directing group to facilitate the dehydrogenative cyclization and inhibit dehydrative cyclization.

Green Protocol for the Friedlaender Synthesis: KAL(SO4)2·12H2O-SiO2 (ALUM-SiO2) A Highly Efficient Catalyst in the Synthesis of Quinolines

In this letter, an efficient synthesis of an array of poly-substituted quinolines from 2-aminoaryl ketones and β-ketoester, β-diketones and α-methylene ketones using KAl(SO4)2·12H2O-SiO2 (Alum-SiO2) u