The synthesis ofN‐containing heterocyclic compounds catalyzed by copper/L‐proline

Abstract

N‐containing heterocyclic compounds are one of the most important motifs prevalent in various bioactive natural products and pharmaceuticals. Given the significance of N‐containing heterocyclic compounds, various synthetic strategies have been developed. Copper/ligand (abbreviated as [CuL])‐catalyzed cascade reaction is a powerful and efficient tool for the construction of N‐containing heterocyclic compounds. L‐proline is one universal ligand and has been utilized in the copper‐catalyzed reactions. In this review, copper/L‐proline‐catalyzed tandem reaction to synthesize the five‐ and six‐membered compounds is emphatically introduced. By comparing the yields in the presence and absence of the ligand, the importance of L‐proline is recorded. Moreover, the function of L‐proline is expounded on the basis of the reaction mechanism from original article.

Diphenhydramine Hydrochloride–CuCl as a New Catalyst for the Synthesis of Tetrahydrocinnolin-5(1H)-ones

“…Copper catalysts have gained widespread consideration over the past years for the synthesis of many important N -heterocyclic compounds due to their low cost, abundance, and low toxicity. , Among them, CuCl, as one of the most commonly used salts of copper, shows tremendous applications in such organic synthesis. − Although CuCl is a suitable and valuable Lewis acid catalyst, it suffers from certain shortcomings like moisture and air sensitivity, which limit its practical applications . However, the combination of CuCl with a species capable of hydrogen bonding can stabilize it, providing an excellent opportunity to improve its catalytic purposes. − …”

Recyclable Magnetic Cu-MOF-74-Catalyzed C(sp2)-N Coupling and Cyclization under Microwave Irradiation: Synthesis of Imidazo[1,2-c]quinazolines and Their Analogues

“…Various synthetic methods of N-fused heterocyclic compounds have been attempted and developed due to their intrinsic biological activities and photoelectronic properties . It is known that imidazole-fused quinazolines, imidazo­[1,2- c ]­quinazolines, also exhibit such biological activities and photoelectronic properties. − However, unlike well-known synthetic methods of each homonuclear component (imidazole and quinazoline) that makes up imidazo­[1,2- c ]­quinazoline, several synthetic methods have been reported for their binuclear N-fused hybrid scaffolds with a limited substrate scope. , Kumar et al reported that 2-(2-bromoaryl)­imidazoles react with formamide in the presence of CuI to produce imidazo­[1,2- c ]­quinazolines via tandem Ullmann-type C–N coupling and intramolecular dehydrative cyclization (Scheme , route a) .…”

Anion‐Templated Self‐Assembly of Silver(I) Frameworks Bridged by μ‐, μ3‐, μ4‐1,2,4,5‐Tetrazine

“…For that, Wu's group reported anion directed Ag(I) complexes and its properties depending on the different anions, and Domasevitch's group reported the formation of anion directed coordination polymers consisting of Ag(I) or Cu(I) and N-heteroaromatic rings derivatives with various anions. [28][29][30] For this purpose, we reported Ag(I)-3,6-dimethoxy-1,2,4,5-tetrazine (dmotz) coordination polymers, where anion π-interaction between the π-acidic dmotz ring and . 31 As a part of our aim for better understanding the role of anion-π interactions in the formation of coordination polymers, we have synthesized coordination polymers using more concise ligand, ttz, and various AgX (X = BF 4 , PF 6 and OTf) salts.…”