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An asymmetric oxidative C-N bond-forming reaction is developed using a chiral diiodospirobiindane derivative as the catalyst and mCPBA as a terminal oxidant. The protocol is based on an asymmetric desymmetrization strategy and affords lactams or spirolactams according to the different substituents on the substrates. The products are obtained in good yields and moderate to high enantioselectivities.

Pterocarine and galeon are typical examples of diarylether heptanoids (DAEHs) with planar chirality due to the strictly constrained conformations in their molecular skeletons. The characterized oxa[1,7]metapara-cyclophane motifs in DAEHs impose great challenges for their enantioselective synthesis. The asymmetric syntheses of (−)-pterocarine and (−)-galeon are demonstrated by employing a chiral phase transfer-catalyzed highly enantioselective SNAr cyclization as the key step for the formation of a diarylether cyclophane skeleton.

A copper-catalyzed intramolecular asymmetric double C-arylation reaction was developed. The method provides a facile approach to chiral spiro bis-oxindoles in high yields and with good to excellent enantioselectivities. It also shows a broad substrate scope and good functional group tolerance. Density functional theory (DFT) calculations were conducted and revealed that the enantioselectivity is determined at the oxidative addition of Cu(I) into the second C–I bond.

Employing a chiral spirodiphosphine monoxide ligand with 1,1'-spirobiindane backbone (SDP(O)), a desymmetrization strategy of Pd-catalyzed intramolecular asymmetric aryl C-O coupling of 2-(2-halophenoxy)propane-1,3-diols, was developed. The SDP(O) ligand shows much better results than its SDP counterpart. The protocol provides an efficient and highly enantioselective method for the synthesis of 2-hydroxymethyl-1,4-benzodioxanes. Density functional theory studies provide a model that accounts for the origin of the enantioselectivity.

An enantioselective intramolecular O-arylation was achieved through desymmetrization with Pd-catalyzed coupling reactions. The intramolecular asymmetric aryl C-O coupling reactions of 2-(2-haloaryl)propane-1,3-diols led to the enantioselective formation of chiral (3,4-dihydro-2H-chromen-3-yl)methanols in good yields and high enantiomeric selectivity.

For the first time, copper-catalyzed intramolecular N-arylation was successfully applied to the kinetic resolution strategy. Under the catalysis of CuI-BINOL derived ligands, the kinetic resolution of rac-2-amino-3-(2-iodoaryl)propionates and rac-2-amino-4-(2-iodoaryl)butanoates afforded chiral intramolecular coupling products and recovered the starting materials in high enantioselectivity (s factors up to 245).

A novel and efficient Pd-catalyzed one-pot reaction of ethyl diazoacetate, isocyanides, and imines for the synthesis of acrylamidines was developed. The multicomponent reaction may have occurred through an unpredicted ring-opening process of the ketenimine-imine [2 + 2] intermediate to form the acrylamidine products.

A simple and efficient approach for the synthesis of [1,2,3]triazolo[1,5-a]quinoxalin-4(5H)-ones is described. The methodology is based on a tandem reaction of 1-(2-haloaryl)propiolamides with sodium azide through a [3 + 2] azide-alkyne cycloaddition and intramolecular Ullmann-type C-N coupling process.

A novel copper-catalyzed tandem reaction of 1-(2-iodoaryl)-2-yn-1-ones with isocyanides is described. The reaction is through a formal [3 + 2] cycloaddition/coupling tandem process and leads to efficient formation of 4-oxo-indeno[1,2-b]pyrroles.

A new and efficient method for the synthesis of aza-fused polycyclic quinolines (e.g., benzimidazo[1,2-a]quinolines) is described. This protocol includes an intermolecular condensation followed by a copper-catalyzed intramolecular C-N coupling reaction. The method is applied to a wide range of 2-iodo, 2-bromo, and 2-chloro aryl aldehyde substrates to yield the aza-fused polycyclic quinolines in good yields.

The differentiation of two nucleophilic amide groups in malonamides through a copper-catalyzed enantioselective intramolecular aryl C–N coupling reaction is demonstrated based on an asymmetric desymmetrization strategy. Such a method afforded enantioenriched 2-oxo-1,2,3,4-tetrahydroquinoline-3-carboxamides in high yields and moderate to good enantioselectivity.

The CuI-catalyzed coupling reaction of vinyl halides with amides or carbamates proceeds well at room temperature to 80 degrees C in dioxane to give enamides using N,N-dimethylglycine as the promoter and Cs(2)CO(3) as the base. The geometry of the C-C double bond is retained during the reaction course. [reaction: see text]

A novel copper-catalyzed tandem reaction was developed by utilizing two famous copper-catalyzed reactions, CuAAC and Ullmann coupling. The trapping of the C–Cu intermediate produced in CuAAC led to further formation of an aryl C–C bond through intramolecular Ullmann C–C coupling.

[reaction: see text] Ullmann-type diaryl ether synthesis can be performed at 90 degrees C using either aryl iodides or aryl bromides as the substrates under the assistance of N,N-dimethylglycine.

[reaction: see text] Ullmann-type aryl amination of aryl iodides and aryl bromides in DMSO at 40-90 degrees C gave the corresponding N-arylamines or N,N-diarylamines in good to excellent yields by using either N-methylglycine or L-proline as the ligand.