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Optimized conditions including the phosphine ligand (PPC) allow the efficient synthesis of trifluoromethylstyrenes from fluorinated vinyl chlorides and arylboronic acids.

A copper(I)-catalyzed aerobic oxidative coupling of ketoxime acetates with simple pyridines for the synthesis of imidazo[1,2-a]pyridines has been developed. This reaction tolerates a wide range of functional groups and it affords a series of valuable imidazo[1,2-a]pyridines in high yields under mild conditions.

A simple and efficient protocol for the fluoroacetylation of indoles is reported. The reaction uses fluorinated acetic acids as the fluoroacetylation reagents to synthesize diverse fluoromethyl indol-3-yl ketones in good yields under catalyst- and additive-free conditions. In addition, the only byproduct is water in this transformation. The synthetic utility of this reaction was also demonstrated by the concise synthesis of α-(trifluoromethyl)(indol-3-yl)methanol and indole-3-carboxylic acid.

A novel palladium(0)-catalyzed dearomative cyclization reaction of bromophenols with (1,n)-diynes has been developed for building two new types of tricyclic architectures containing a quaternary carbon center. This method employs inexpensive bromophenols, and easily accessible tethered diynes. It exhibits a broad substrate scope and tolerates various functional groups. Preliminary results with commercially available chiral ligands indicate that enantioselective variants are feasible for both cyclization processes.

A novel Pd(0)-catalyzed intermolecular carbocyclization of phenol-derived biaryls with 1,3-dienes has been implemented through a sequence of oxidative addition to the C-I bond, regioselective olefin insertion, and allylative dearomatization. This method provides a broad range of attractive spirocyclic compounds bearing two contiguous tertiary/quaternary carbon centers in good yields with excellent chemoselectivity and regioselectivity. Moreover, preliminary results indicate that asymmetric control of this process is feasible with chiral ligands.

A novel and efficient copper-catalyzed radical cross-coupling of 1,3-dicarbonyl compounds with terminal alkenes for the synthesis of tetracarbonyl compounds with a quaternary carbon atom has been developed. Mechanistically, this transformation involves the construction of two C–C bonds and two CO bonds in a one-pot process. The reaction tolerates a wide range of functional groups and proceeds under mild conditions.

A novel and efficient iron-catalyzed cyclization of ketoxime carboxylates and N,N-dialkylanilines for the modular synthesis of diverse pyridines was developed. The reaction was initiated by Fe-catalyzed N–O bond cleavage of ketoxime carboxylates in the presence of tertiary anilines. The methylene carbon on N,N-dialkylanilines functioned as a source of one-carbon synthon in the reaction. The reaction used readily available starting materials, tolerated various functional groups, and afforded 2,4-disubstituted and 2,4,6-trisubstituted pyridines in good to high yields under mild conditions.

A novel palladium(II)-catalyzed [5+2] oxidative annulation of readily available o-arylanilines with alkynes has been developed for building a seven-membered N-heterocyclic architecture containing a biaryl linkage. This method is applicable to a wide range of unprotected o-arylanilines and internal alkynes, and results in the chemoselective preparation of imine-containing dibenzo[b,d]azepines in high yields with excellent diastereoselectivity with respect to the two types of stereogenic elements.

The palladium-catalyzed oxidative Heck reaction of 2,3,3,3-tetrafluoroprop-1-ene with various arylboronic acids was explored for the first time. This method provides a direct route to access (Z)-β-fluoro-β-(trifluoromethyl)styrenes with high stereoselectivity.

The first dynamic kinetic asymmetric transformation of racemic biaryl substrates on the basis of axial-to-central chirality transfer has been realized. Chiral Pd-NHC complexes were found to catalyze the dynamic kinetic asymmetric spiroannulation of 4-(2-bromoaryl)-naphthalen-1-ols (or 2′-bromo-[1,1′-biphenyl]-4-ols) with internal alkynes, affording a series of enantioenriched spirocyclic products bearing an all-carbon quaternary stereocenter in good yields (up to 95%) with excellent enantioselectivities (up to 97% ee).

An intermolecular spiroannulation reaction of appropriately substituted 2-arylphenols with internal alkynes has been developed by using a Ru(II) catalyst and an oxidant. This transformation was realized by a phenol-directed C–H activation, migratory insertion of the alkyne, and subsequent dearomatization of the phenolic ring, providing a broad range of highly functionalized spirocyclic compounds in moderate yields with high regioselectivity.

A simple and efficient procedure is elaborated for the microwave-assisted synthesis of spirocyclic compounds (III) and (V) from naphthols and symmetrical alkynes.

Catalytic asymmetric aminative dearomatization of 1-substituted 2-naphthols is successfully implemented with electrophilic azodicarboxylates under the catalysis of chiral ScIII/pybox complexes.

Various aliphatic alcohols and phenol (XIIIb) can be used under CO atmosphere in the presence of Pd(O-Ac)2 as an optimal catalyst.

The novel [2+2+1] spiroannulation reaction of naphthols with alkynes succeeds using symmetrical diaryl and dialkyl alkynes.Mixed aryl-alkyl alkynes provide three regioisomeric products one of which is formed with moderate to good excess (not shown).

A p-TsOH-mediated 1,3-dipolar cycloaddition of nitroolefins and sodium azide for the synthesis of 4-aryl-NH-1,2,3-triazoles has been developed. p-TsOH was discovered as a vital additive in this type of 1,3-dipolar cycloaddition. This novel cycloaddition reaction is a good method for the rapid synthesis of valuable 4-aryl-NH-1,2,3-triazoles in high yields.

A copper-catalyzed cascade coupling and aerobic oxidation of aromatic nitriles and 2-aminobenzylamine for the synthesis of 3,4-dihydroquinazolines and quinazolineshas been achieved. The catalytic system, characterized by not adding additives and using molecular oxygen as the sole oxidant, exhibited exquisite substrate specificity and operated under mild conditions through inherently “green” processes.

Reaction conditions A) and B) are found to be highly efficient for the preparation of various title compounds including the high-affinity 5-HT3 receptor antagonist (XVI), which are not easily accessible by traditional procedures.

A facile benzoyl peroxide (BPO) mediated ortho-hydroxylation and benzoylation of N-alkyl anilines for the synthesis of 2-benzamidophenols has been developed. The reaction tolerates a wide range of functional groups and is a good method for the straightforward synthesis of valuable 2-benzamidophenols in good yields under mild conditions.

A novel and efficient Cu-catalyzed intermolecular 5-endo-trig cyclization of ketoxime carboxylates for the synthesis of 2-arylpyrroles is developed.

The synthesis of tetrasubstituted symmetrical pyridines by a novel ruthenium-catalyzed cyclization of ketoxime carboxylates with DMF is described.

A novel palladium-catalyzed oxidative double carbonylation of o-iodoanilines for the synthesis of isatoic anhydrides has been developed. The reaction employs readily available o-iodoanilines as the starting materials and proceeds under mild conditions. For extension, palladium-catalyzed oxidative carbonylation of anthranilic acids was developed for the synthesis of substituted isatoic anhydrides in high to excellent yields.

An efficient copper-promoted oxidative coupling of enamides with alkynes has been developed for the synthesis of substituted pyrroles. The reaction proceeded through C-H and N-H bond functionalization of enamides under mild conditions.

A novel and efficient palladium-catalyzed aminocarbonylation of aryl iodides with amides and N-alkyl anilines has been developed. The reaction tolerates a wide range of functional groups and is a reliable method for the rapid synthesis of a variety of valuable imides and tertiary benzanilides under an atmospheric pressure of CO.

The method is only applicable to aryl-substituted enamides, whereas aliphatic ones do not react.

In contrast to monoalkylmonoarylketoxime carboxylates, dialkylketoxime carboxylates do not react under the employed conditions.

The FeCl3-catalyzed self-condensation of enamides offers a new strategy for the synthesis of enamido-substituted nitrogen-containing quaternary carbon centers, which are attractive structures in organic chemistry. The reaction affords nitrogen-containing quaternary carbon centers in good yields under mild reaction conditions. The catalytic system was also employed in the condensation of enamides with indoles for the synthesis of bis-indoles.

A novel Cu(TFA)2-catalyzed oxidative tandem cyclization/1,2-alkyl migration of readily available enamino amides for the synthesis of pyrrolin-4-ones has been developed. The reaction tolerates a wide range of functional groups and is a reliable method for the rapid synthesis of substituted pyrrolin-4-ones in high yields under mild conditions.

A novel and efficient method for the oxidation of 2-arylindoles to synthesize 2-arylbenzoxazinones utilizing oxone as the sole oxidant has been developed. The reaction tolerates a wide range of functional groups and allows quick and atom-economical assembly of a variety of valuable 2-arylbenzoxazinones in high yields.

The novel and efficient title synthesis affords regioselectively Z-iodoenamides from readily available ketoximes.

Molecular braids represent one of the most fascinating topological networks in the fields of supramolecular chemistry and crystal engineering. In this Tutorial Review we provide an overview of the sustainable exploration of those metal–organic frameworks (MOFs) with the topology of molecular braid. Since the first example of the triple-stranded molecular braid in MOFs was reported by our group in 2005, another five attractive molecular braids in MOFs have already been prepared through several different pathways by us and other groups. Indeed, these known examples include the triple-, quintuple- and sextuple-stranded molecular braids. Besides the molecular braids found in MOFs, this type of unique topological network was also observed in organic co-crystals, and the only example of this is discussed in context as well.

A novel and general procedure for Cu-catalyzed coupling of enamides with alkynes to synthesize substituted pyridines was developed. The chemistry was allowed to extend to the synthesis of substituted isoquinolines by coupling of enamides with arynes under transition-metal-free conditions.

Switchable access to carbamates and ureas has been developed by solvent control palladium-catalyzed carbonylation of aromatic amines under an atmosphere of carbon monoxide. A variety of N-phenylcarbamates and N,N′-diphenylureas was easily synthesized in good to excellent yields from readily available aromatic amines under mild conditions.

A wide range of triarylsubstituted pyridine derivatives and fused pentacyclic products is prepared.

CuI-catalyzed reductive acylation of ketoximes for preparation of enamides was reported. A broad scope of enamides was obtained in high yields with NaHSO3 used as the terminal reductant.

The title compound 1 underwent an insertion reaction with dichlorocarbene selectively at the C-4 double bond. The [4 + 2]cycloadditions of 1 with benzoquinone and naphthoquinone proceeded by subsequent dehydrocyanation and oxidative aromatization under mild conditions to give the diarylamines 6 and 7. The cycloaddition of 1 and N-phenylmaleimide in a sealed tube proceeded with reinsertion of the cyanide ion to give the diarylamine 8. The homologation of 1 with chlorosulfonyl isocyanate (CSI) and tetracyanoethylene (TCNE), giving the dienoate 9 and the triene 10, was unusual compared with commonly observed [2 + 2]cycloadditions of CSI and TCNE. The reaction of 1 with dimethyl acetylenedicarboxylate proceeded via an intermediate cyclobutene and tandem ring-opening afforded the triene 11. The reaction of 1 with ethyl propiolate produced two diarylamines 12a and 12b. Formation of 12a might involve cyanide reinsertion on the intermediate derived from the [4 + 2]cycloaddition, whereas an opening of the [2 + 2] intermediate followed by an electrocyclization would yield the isomer 12b.

Tandem Michael additions of indole derivatives to 3-nitrocoumarins 2, followed by MVK, in one pot, has been developed for the synthesis of multi-functionalized 3,4-dihydrocoumarins bearing a quaternary stereocenter. The reaction proceeds with high diastereoselectivities in good to excellent yields.