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An efficient and versatile method for the assembly of novel polycyclic benzimidazole derivatives has been developed by Cu-catalyzed domino addition/double cyclization reactions. A wide variety of polycyclic benzimidazole derivatives, which might be used as synthetic medicines and functional materials, were successfully assembled from bis-(o-haloaryl)carbodiimides. Unexpected N-methylated benzo[4,5]imidazo[1,2-a]indoles can also be selectively assembled. Multibonds and polycyclic moieties were conveniently formed in one pot during these domino processes.

A mild and efficient Cu(2)O-catalyzed domino intramolecular C-N coupling/C-Y (Y = O, S, N) bond formation was successfully achieved. Thus oxazino[3,2-a]indole, thiazino[3,2-a]indole and indolo[2,1-b]quinazoline derivatives were facilely assembled from readily accessible gem-dibromovinyl systems. The protocol is general and practical, affording a variety of the indole-incorporated products in good to excellent yields even under air atmosphere.

A one-pot synthesis of unsymmetrical 2,2'-biindolyl derivatives through a Cu-catalyzed N-arylation/Pd-catalyzed direct arylation sequence was described. The reaction involved easily prepared o-gem-dibromovinyl substrates, and the desired biindolyls were obtained in moderate to good yields.

A new rhodamine B-based dual-function chromo- and fluorogenic probe for Cu(2+) and ClO(-) has been designed, synthesized, and characterized. The probe comprises a spectroscopic unit of rhodamine B and a Cu(2+)-specific chelating unit of pyridinecarboxamide as well as a ClO(-)-specific reactive moiety of diacylhydrazine, and is a highly selective and extremely sensitive fluorescent and colorimetric sensor for Cu(2+) and ClO(-) in different pH conditions. Compared with the reported probes for Cu(2+) or ClO(-), this is the first chemosensor based on a small molecule that can detect both Cu(2+) and ClO(-), respectively, at 1 nM level.

A novel and efficient one-pot synthesis of various N-substituted 2-heterobenzimidazoles has been developed. Through a Cu(I)-catalyzed cascade intermolecular addition/intramolecular C-N coupling process, a wide variety of 2-heterobenzimidazoles could be synthesized from o-haloarylcarbodiimides and N- or O-nucleophiles.

Employing ethyl 2-oxocyclohexanecarboxylate as a novel, efficient, and versatile ligand, the copper-catalyzed coupling reactions of various N/O/S nucleophilic reagents with aryl halides could be successfully carried out under mild conditions. A variety of products including N-arylamides, N-arylimidazoles, aryl ethers, and aryl thioethers were synthesized in good to excellent yields.

Direct C−H functionalization is an important strategy for the rapid synthesis of valuable organic molecules. Radical‐involved remote C(sp3)‐H functionalization based on hydrogen atom transfer (HAT) becomes an important method enabling selective direct transformation of C(sp3)‐H bonds at specific distal position(s). In the recent years, copper‐catalyzed fluoroamide‐directed remote C(sp3)‐H bond functionalization through intramolecular HAT has served as a robust and elegant strategy for the assembly of a variety of functionalized (sulfon)amides and related derivatives. This review focuses on the recent advances in this area. These transformations proceed effectively with high selectivities and good functional group compatibility under mild conditions. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Fused polycyclic N‐heterocycles are very important scaffolds in biomedicinal chemistry and materials science. Intramolecular alkyne hydroamination is a powerful method for the construction of N‐heterocycles. In the last two decades, copper‐catalyzed domino reactions based on intramolecular alkyne hydroamination has emerged as a robust strategy for assembling various fused polycyclic N‐heterocycles. Great progress has been achieved in this area. This short review covers the advances made in copper‐catalyzed domino synthesis of fused polycyclic N‐heterocycles based on the strategy from 2008 to 2023, and will hopefully serve as an inspiration towards the exploration of new copper‐catalyzed versions of the transformation. The domino transformations are introduced and discussed from five aspects according to the different key processes involved in these reactions. [ABSTRACT FROM AUTHOR]

Herein, we describe the development of a copper‐catalyzed C(sp3)‐amination of proaromatic dihydroquinazolinones derived from ketones. The reaction is enabled by the intermediacy of open‐shell species arising from homolytic C−C bond‐cleavage driven by aromatization. The protocol is characterized by its operational simplicity and generality, including chemical diversification of advanced intermediates. [ABSTRACT FROM AUTHOR]

C17H16CuN6OS ⋅ 0.5H2O, monoclinic, P21/c (no. 14), a = 10.3523(4) Å, b = 18.2609(9) Å, c = 9.9688(4) Å, β = 103.918(4)°, Z = 4, V = 1829.21(13) Å3, Rgt(F) = 0.0409, wRref(F2) = 0.1099, T = 291(2) K. [ABSTRACT FROM AUTHOR]

C34H32Cu2N12O2S2, triclinic, P1 (no. 2), a = 7.7970(7) Å, b = 9.6110(9) Å, c = 12.7629(12) Å, α = 71.544(8)°, β = 79.322(8)°, γ = 83.734(8)°, Z = 1, V = 890.21(14) Å3, Rgt(F) = 0.0634, wRref(F2) = 0.1827, T = 291(2) K. [ABSTRACT FROM AUTHOR]

A copper(I)-catalysed domino transformation for the synthesis of tricyclic imidazobenzimidazole derivatives was developed. Using readily available primary propargylic amines and o-haloarylcarbodiimides as the starting materials, a variety of substituted benzo[ d]imidazo[1,2- a]imidazoles was efficiently and selectively assembled. Further investigations indicated that the domino reaction was likely the result of a novel addition/cycloisomerisation/coupling process. [ABSTRACT FROM AUTHOR]

A variety of substituted quinoline/pyridine, thiochromene and naphthalene derivatives, which might be of biological and medicinal value, were synthesized by copper-catalyzed domino SN2′/coupling, SN2′/deacylation/coupling and SN2′/coupling/elimination reactions. The method provides a general and convenient approach to the synthesis of various substituted cyclic compounds from the corresponding Baylis-Hillman (B-H) acetates and N-/S-/C-nucleophiles. [ABSTRACT FROM AUTHOR]

Although the electrokinetic (EK) remediation has drawn great attention because of its good maneuverability, the focusing phenomenon near the cathode and low removal efficiency remain to be addressed. In this study, a novel EK reactor was proposed to remediate Cu and Pb contaminated loess where a biological permeable reactive barrier (bio-PRB) was deployed to the middle of the EK reactor. For comparison, three test configurations, namely, CG, TG-1, and TG-2, were available. CG considered the multiple enzyme-induced carbonate precipitation (EICP) treatments, while TG-1 considered both the multiple EICP treatments and pH regulation. TG-2 further considered NH 4 + recovery based on TG-1. CG not only improved Cu and Pb removals by the bio-PRB but also depressed the focusing phenomenon. TG-1 causes more Cu2+ and Pb2+ to migrate toward the bio-PRB and aggravates Cu and Pb removals by the bio-PRB, depressing the focusing phenomenon. TG-2 depressed the focusing phenomenon the most because Cu2+ and Pb2+ can combine with not only CO 3 2− but PO 4 3−. The removal efficiency of Cu and Pb is 34% and 36%, respectively. A NH 4 + recovery of about 100% is attained. • EK-bio-PRB technology is used to remediate Cu- or Pb-contaminated loess. • The effect of pH regulation depresses the focusing effect near the cathode. • Cu2+ and Pb2+ can combine with not only CO 3 2− but also PO 4 3− under NH 4 + recovery. • The bio-PRB improves Cu and Pb removals by 8.5% and 12.8% respectively. • A NH 4 + recovery of about 100% is attained toward preventing secondary pollution. [ABSTRACT FROM AUTHOR]

A convenient, inexpensive and effective approach to the synthesis of 2- o -cyanoaryl oxazole derivatives has been developed. Generally, the copper-mediated cyclization/coupling reactions afforded corresponding 2-cyanoaryl oxazoles and oxazolines in moderate to excellent yields. The functionalized oxazole derivatives may be useful in biological chemistry and medicinal science. Our investigation indicates that the formation of the oxazole ring might favor the C C bond forming process on the ortho -position of the aryl ring. And CuCN plays dual roles as a Lewis acid catalyst and a C -nucleophile in this transformation. [ABSTRACT FROM AUTHOR]