The N-arylsulfonamide group is an important moiety in medicinal chemistry because of its presence in many useful molecules with potential bioactivities. As a result, the development of synthetic routes to N-arylsulfonamides has been actively investigated. In recent years, the transition metal-catalyzed sulfonamidations of aryl halides, arylboronic acids and C_Ar-H bonds have extensively investigated, providing more efficient and environmentally friendly procedures for the synthesis of N-arylsulfonamides. The recent progress in the transition metal-catalyzed sulfonamidation reactions is reviewed. The aromatic substrates, transition metal-catalysts, ligands, sulfonamidating reagents, mechanisms of the sulfonamidation reactions are mainly discussed. Finally, the future development of them is also prospected.

The C=C double bond cleavage of NH₂-functionalized enaminones has been realized at room temperature to provide various N-sulfonyl amidines by reacting with sulfonyl azides. The reactions take place with good substrate tolerance in the presence of 1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU) without any metal or oxidant reagent. The ¹⁵N-labelling experiment on enaminone indicates that the sulfonyl azide component donates solely the sulfonamide fragment, and the reaction mechanism involving a key decomposition of the in situ generated 1,2,3-triazoline intermediate is convictively supported.

Transition metal complexes-catalyzed homogeneous asymmetric hydrogenation is an important method for the synthesis of chiral compounds. At present, it is mainly focused on precious transition metal catalytic systems, such as ruthenium, rhodium, iridium and palladium. However, they are suffered from the difficulties of limited resource, high cost and environmental contamination. Therefore, it is important and necessary to develop catalytic systems based on cheap, non-toxic or low toxic, environmentally friendly and earth-abundant iron, cobalt, nickel, copper transition metal, which are in accordance with the requirements and research trend of the sustainable development of modern chemistry. The recent progress of nickel-catalyzed homogeneous asymmetric hydrogenation of prochiral unsaturated compounds containing carbon oxygen double bond (C=O), carbon carbon double bond (C=C) and carbon nitrogen double bond (C=N) is reviewed, and some breakthroughs and considerable research results achieved are introduced. In addition, the advantages and disadvantages of different types of substrates in nickel catalyst system are analyzed, and the future research direction is prospected.

A novel method of copper-catalyzed cyclization of 1-aryl-1-cycloalcohols and 1,3-dicarbonyl compounds has been developed, affording various cycloalkane-fused dihydrofurans in moderate to excellent yields. This transformation proceeds under mild conditions and with a good tolerance of functional groups. The mechanistic investigation revealed that the reaction involved radical intermediates.

A nickel-catalyzed Negishi coupling of cyclobutanone oxime esters with aryl zinc reagents has been developed, in which nickel serves both as an initiator for imine radicals and a catalyst for the coupling of aryl zinc reagents with oxime esters. The protocol can avoid the use of poisonous cyanide and has broad substrate scope as well as good functional group compatibility. Therefore, this method provides an attractive strategy for the synthesis of valuable nitriles. Preliminary mechanistic studies indicate that a radical pathway is involved in the product formation.

Carbazole and its derivatives are widely used in the field of medicine and photoelectric materials. A kind of stable cyclic hypervalent iodine reagents containing carbazole group was developed, which belong to benziodoxole compounds. In the presence of Cu(I) catalyst, these reagents reacted with aromatic substrates to give N-aryl carbazole derivatives. The reaction conditions are mild and suitable for a variety of electron-rich arenes. And a radical mechanism was proposed.

A phosphine-mediated Staudinger/Aza-Michael addition of azides with trifluoromethyl substituted α,β-unsaturated ketones was developed, giving hydroamination products in medium to good yields (up to 96%). The hydroamination products could be prepared on gram scale and a wide range of substrates are tolerated under the optimized reaction conditions (30 examples). ³¹P NMR experiments indicate that this reaction was initiated by Staudinger reaction of azide with phosphine.

Pyrazole, an important class of nitrogen-containing five-member hetrocyclic compounds, widely exists in natural products, bio-active molecules and drugs, and it is also a valuable intermediate in organic synthesis. The synthesis of polysubstituted pyrazoles has attracted much attention and developed rapidly in recent years. Herein, the recent research progress in the construction of polysubstituted pyrazoles is summarized.

Catalytic asymmetric hydrofunctionalization of alkene is an important research field, which enables efficient construction of chiral molecules from readily available starting materials. Asymmetric hydrofunctionalization of multiple substituted alkenes represents a significant challenge to organic chemists because this process involves the simutaneous control of regio-, diastereo-, and enantio-selectivities. The key to solve this challenge is to identify novel catalyst systems to exert powerful regio- and stereo-control. Recently, by taking advantage of substrate-directed strategy, we have developed a number of alkene functionalization methods with excellent regio-, diastereo-, and enantio-selectivities. In particular, we focus on catalytic asymmetric hydroalkynylation of alkenes as a model transformation to analyze the factors that control the selectivity.

A novel palladium(0)-catalyzed dearomative spirocyclization reaction of bromophenols has been developed for building a series of spirocyclic architectures containing a quaternary carbon center via[2+2+1] strategy. This method employs inexpensive bromophenols and easily accessible alkynes. It exhibits a broad substrate scope in good yields. Notably, this transformation can be realized with high regioselectivity (>19:1 rr) when using unsymmetrical alkynes, which greatly expands the research scope of phenol dearomatization.

3-(5-Oxazolyl)indole-type natural products such as pimprinine and streptochlorin, widely exist in marine microorganism, because of their diverse biological activity, 3-(5-oxazolyl)indoles show good research and development potential in the field of medicine and pesticide. Numerous studies have been performed to synthesize 3-(5-oxazolyl)indole-type natural products, in which the construction of indole ring and oxazole ring is the most important part. In this paper, the reported natural products with 3-(5-oxazolyl)indole skeleton structure and their biological activities are summarized, and the synthetic methods for 3-(5-oxazolyl)indole skeleton and some of their mechanism are also reviewed. The application prospect of 3-(5-oxazol-yl)indole as a dominant active structure in the future was discussed.

Chiral aryl alcohols are prevalent in a broad range of biologically active compounds, pharmaceutical agents and natural products. They also constitute a broad class of optically active building blocks for the synthesis of important chiral compounds. In recent years, organoboron reagents are widely used in organic synthesis as they possess advantages of ready availability, low toxicity, good air and moisture stability as well as high functional group compatibility. Since the first report of rhodium-catalyzed asymmetric addition of aryl boronic acids to aryl aldehydes in 1998 by Miyaura, the use of organoboron reagents in asymmetric addition to various carbonyl compounds under various transition-metal catalyses has been intensively investigated. Over the past two decades, transition metal-catalyzed asymmetric addition of organoboron reagents to aldehydes and ketones has proved as one of the most direct and powerful methods for accessing versatile optically active alcohols. The development and progress of a wide range of chiral ligands for Rh, Ru, Pd, Ir, Cu, Ni and Co catalysis for asymmetric addition of organoboron reagents to aldehydes and ketones are summarized, and the achievements in enantioselective synthesis of chiral aryl alcohols and their applications in the synthesis of related biocative products are described. Among them, rhodium and ruthenium-catalyzed enantioselective additions have received considerable attention. In the cases of activated carbonyl compounds such as α-aryl ketoesters and α-diaryl diketones, excellent results can be attained in terms of both yield and enantioselectivity. However, it remains a daunting challenge for highly enantioselective addition to simple unactivated aldehydes and ketones owing to the difficulty in overcoming stereo differentiation. Future efforts in the community would focus on developing new effective transition-metal catalysts in addressing these issues by promoting efficient transformation and controlling excellent enantioselectivity.

The development of efficient methods for the preparation of unnatural amino acids has long been an important goal since their widely application in synthetic and medicinal chemistry. The asymmetric α-functionalization of nucleophilic metalated azomethine ylides, which could be in situ-generated from readily-available aldimine esters, has been recogonized as a powerful strategy to synthesize unnatural amino acids. Over the past 20 years, tranistion metal-catalyzed asymmetric construction of unnatural amino acids using azomethine ylides have been extensively studied. In this review, the progress on metallated azomethine ylides invovled aymmetric transformation for the synthesis of unnatural amino acids is summarized according to eletrophilic reagents.

A series of thiazolo[3,2-a]pyrimidine derivatives were synthesized from the reaction of α-bromoacetophenone, aromatic aldehyde, malononitrile and thiourea which was catalyzed by Tröger's base derivative 5,12-dimethyl-3,10-diphenyl- bis-1H-pyrazol[b,f] [4,5]-1,5- diazadicyclo[3.3.1]-2,6-octadiene (1). The reaction mechanism was discussed by the ¹H NMR analysis and chemical experiments. The pharmacological activity results of the products indicated that most of products showed high inhibitory on one or more cancer cells in human hepatocarcinoma cell (HepG2), human non-small cell lung cancer cell (247) and human non-small cell lung cancer cell (A549) in vitro. And seven products have antibacterial activity against the methicillin-resistant Staphylococcus aureus. These results showed the great potential of these compounds in drug development.

N-O bond cleavage is one of the most efficient and powerful strategies to introduce N-or O-functional groups into molecules in organic synthesis. Copper catalyst, as the abundant in earth and inexpensive advantages has been widely used to construct C-N and C-O bond. Furthermore, N-O bond cleavage has been successfully applied in the total synthesis of natural products and pharmaceuticals. The new development of copper-catalyzed N-O bond cleavage and its application in the total synthesis of natural products and pharmaceuticals in recent years have been summarized.

Pure organic luminescent supramolecular materials with either phosphorescence or fluorescence emission have become a hot research topic due to their low toxity, facile preparation and wide applications. In recent years, our group has designed several novel luminescent macromolecules, achieving tunable multi-color emission. For the construction of phosphorescent materials, heavy atoms such as bromine and iodine as well as other hetroatoms with lone pair electrons like oxygen were employed to facilitate the intersystem crossing (ISC) process of the luminophores while rigid environments were provided via host-guest interactions and polymerization to restrict molecular motions, which results in reduced nonradiative decay. Moreover, noncovalent interactions are stimuli responsive because of their dynamic nature. Therefore, host-guest interactions, along with other noncovalent interactions including hydrophobic effects, π-π stacking and multiple hydrogen bonding, were also used for adjusting the intensities and wavelengths of phosphorescence or fluorescence, achieving diverse luminescence properties that the luminophore itself does not possess. This account summarizes the above advances and proposes possible directions for further research, like not only improving quantum yields but also expanding the range of emission wavelength of organic phosphorescent materials and developing luminescent materials that can intelligently respond to external stimuli.

The phosphine-catalyzed[3+2] annulation of γ-methyl allenoates with 2-arylidene-1H-indene-1,3(2H)-diones is reported. In the reaction, a series of highly functionalized spiro[4.4]dec-6-ene skeletons were obtained in moderate to good yields and high diastereoselectivities. It should be noted that the perfect α-regioselective annulation adducts were obtained with simple PPh₃ catalyst.

Thiocyanate, as a versatile synthon, which has important application value in many fields such as pharmaceutical, pesticide and materials. The photocatalytic and electrocatalytic thiocyanation reactions have been widely concerned in organic chemistry due to the advantages of green, efficiency and safety. In this review, the cross-coupling/thiocyanation reactions based on the photocatalytic and electrocatalytic are described, which is expected to be helpful in exploring the green synthesis of thiocyanates compounds.

Aspirin (ASP), the first synthetic drug, is widely used as a non steroidal anti-inflammatory drug. It displays a variety of biological activities, such as anti-thrombosis, anti-inflammatory, anti-tumor, etc. A lot of works about the synthesis and related activity evaluation of its derivatives were reported. There are four kinds of derivatization methods:skeleton derivatization, prodrug derivatization, twin derivatization and metal coordination derivatization. According to the different modification sites, skeleton derivatization could be further divided into C(1)-COOH site modification, C(1)-COOH site and C(2)-OAc site simultaneous modification, C(2)-OAc site modification and benzene ring modification. NO-ASP is the main method to prepare antithrombotic derivatives, and metal coordination modification is the main synthesis scheme of anticancer derivatives. The structure modification and bioactivity research of aspirin in recent twenty years and the synthetic routes of 353 aspirin derivatives and the pharmacological activities of some derivatives are described, which provides a reference for the further development of aspirin derivatives.

As interesting synthetic targets, dimeric cyclotryptamine alkaloids bearing sterically hindered vicinal all-carbon quaternary stereocenters have attracted significant attention from the synthetic community. Stereocontrolled synthesis of the congested all-carbon quaternary stereocenters in these alkaloids presents a formidable challenge. This review summarizes the synthetic efforts towards dimeric cyclotryptamine alkaloids in the last twelve years.

Transition-metal-catalyzed Suzuki-Miyaura cross-coupling is one of the most powerful transformations for C-C biaryl bond formation at present. With the increasing demand for green chemistry, water as solvent for the Suzuki-Miyaura cross-coupling reactions has been of widespread interest. The literature in recent years on the Suzuki-Miyaura cross-coupling reactions by heterogeneous or homogeneous catalysis in water is reviewed, and their perspectives for further developments are also presented.

Visible-light-promoted organic synthesis is an important research hotspot and frontier in organic chemistry in recent years. Particularly, as a novel organic photosensitizer, 2, 4, 5, 6-tetrakis(carbazol-9-yl)-1, 3-dicyanobenzene (4CzIPN) has showed excellent catalytic performance in visible-light-induced radical reactions. The recent progress on the transition-metal-free photosynthesis under visible-light catalyzed by 4CzIPN is reviewed, and the application of 4CzIPN for photocatalytic organic transformations from different precursors (including silicon reagent, carboxylic acid and its derivatives, sulfur-containing reagent and fluorine reagent) is included.

Phenazine-1-carboxylic acid (PCA) as a natural product widely exists in microbial metabolites of Pseudomonads and Streptomycetes, which displays potent inhibitory activities against plant pathogens, and has medical antibacterial and antitumor effects, and so on. In this review, the biosynthesis and chemosynthesis of phenazine-1-carboxylic acid are summarized. At the same time, the diverse biological evaluations of its biosynthetic and chemosynthetic analogues are summarized, which could provide reference for the study of structural modifications and biological activities of these analogues.

Benzofulvenes were widely found in natural products and bioactive molecules, and also served as important building blocks in material science and transition-metal chemistry. Great efforts have been devoted to the efficient synthesis of these interesting molecules, and rapid advancement has been made in the past two decades. According to the types of the initiation of the reaction, these methods can roughly be classified into five categories:thermal or photochemical cyclization of enyne-al-lenes or enediynes, transition metal-catalyzed sequential cyclization reaction, electrophilic or nucleophilic attack initiated cyclization, radical initiated cyclization and acid promoted cyclization. This review describes the important synthetic methods of benzofulvenes according to their reaction types.

Oxygen-bearing structures are attractive synthetic targets due to their wide presence in a great number of natural products and biologically active molecules, and their role as useful synthons in organic synthesis. Thus, the preparation of O-bearing compounds has been an important topic. Transition metal-catalyzed aerobic oxygenation strategy has emerged as a novel and efficient methodology for constructing C-C bonds and C-heteroatom bonds. This strategy has become one of the most important and useful synthetic method in organic synthesis of O-bearing compounds. Based on the previous work of our group and others, herein, the new applications of transition metal-catalyzed oxygenation of C-H bond activation and C-C bond cleavage with oxygen as oxygen source are discussed. The recent progress in trans-metal catalytic oxygen insertion of ketones, aldehydes, alkene, alkynes, arene and aromatic heterocyclic compounds has been reviewed. Transition metal-catalysts can initiate oxygen insertion reaction of free radical pathway and realize selective insertion of oxygen radicals under oxygen oxidation. These reactions are characterized by mild conditions, environmental protection and highly atom economy.

The C-H activation assisted by directing groups is an important measure for selective C-H activation at specific positions, and it is also one of the hot spots in the research field of organic chemistry. As an efficient directing group, carboxylic acid has the advantages of low cost, low toxicity, easy modification and using as traceless directing groups. Recent development on C-H functionalization directed by carboxyl group according to different coupling modes is summarized, and the representative reaction mechanism is briefly described. Existing problems with a brief outlook in this field are also presented.

Scientists have found more and more sulfur compounds in food with the development of science and technology, high-precision analytical methods and equipment. In 2015, Flavor and Extract Manufactures Association of the United State published 2816 safe flavors, and there are more than 388 sulfur-containing compounds, accounting for more than 13%. The main smell of sulfur-containing flavors is food, especially the non-staple food and dishes. It is mainly used as food flavor, flower flavor and fruity flavor. Due to the increase of sulfur-containing perfume and flavors demand, its production scale is increasing, the research on synthesis methods is also deepening, and the green and efficient construction methods are also constantly reported. In this review, the recent progress in the construction of sulfide, thiol, thioester and polysulfide perfume & flavors is summarized.

α-Amino acids are the units of proteins, which not only widely occur in many biological important compounds and natural products, but also are useful as organic catalysts or ligands for asymmetric synthesis. Among them, glycines are particularly useful building blocks in organic synthesis. Direct C(sp³)-H bond functionalization of glycine derivatives provided an attractive synthesis strategy for the construction of a variety of α-substituted α-amino acids. The recent progress in the α-C(sp³)-H bond activation of glycine derivatives, with various reagents to form carbon-carbon and carbon-heteroatom bond, and oxidative coupling/cyclization reaction involving glycine derivatives is reviewed.

The cross dehydrogenation coupling reaction realizes direct coupling of two different X-H bonds to form a new chemical bond, thus featuring excellent step and atom economy. The traditional cross dehydrogenation coupling reaction was usually catalyzed by transition metal, which had the problems of expensive catalyst and serious pollution. Visible light-induced electron transfer is also an effective way to realize direct functionalization of X-H bonds. Visible-light-induced cross dehydrogenation coupling reaction under transition metal-free conditions is widely concerned due to the advantages of cleanliness, safety as well as high step and atom economy. Classified by the type of bonding, the research progress of these reactions is reviewed, and their future outlook is also discussed.

Synthesis of complex molecules via multicomponent reactions (MCRs) in a one-pot reaction manner has emerged as an important means to realize the value-added conversion of cheap and easily available renewable bio-based platform molecules. The diversity and multi-functionality of these biomass-derived molecules provide a fascinating platform for establishing MCRs, and in many cases, the developed MCRs would not be attained from less functionalized substrates. This review introduces some typical examples for the conversion of biomass-derived platform compounds to high value-added products through MCRs. It mainly summarizes the MCRs developed by using polyols, dicarboxylic acids, levulinic acid and furfural derivatives as one of the starting substrates. At the end of this review, a perspective of this direction is also given.

Recently, the direct sulfenylation of C——H bond for C——S formation under transition metal-free conditions has rapidly advanced and is employed for eco-friendly synthesis of sulfenylated natural or bioactive compounds with various sulfenylating reagents. In particular, the sulfenylation of indoles is considered to be the most important because it can lead to a new class of molecules displaying a broad spectrum of biological and pharmaceutical activities. The recent five-year progress in direct C——H bond sulfenylation of indoles under transition metal-free conditions is discussed and their mechanisms in detail are described.

Compounds bearing difluoromethylthio (SCF₂H) and monofluoromethylthio (SCFH₂) groups are potentially important targets in the pharmaceutical and agrochemical fields due to their unique physical and chemical properties. The traditional methods of synthesizing these two kinds of compounds are difluoromethylation and monofluoromethylation of sulfhydryl substrates. However, the limitation of sulfhydryl substrates also limited the application and development of such compounds. Thus, it is still highly desirable to develop new methods for difluoromethylthiolation and monofluoromethylthiolation as well as new types of difluoromethylthiolation and monofluoromethylthiolation reagents. The recent development of direct difluoromethylthiolation and monofluoromethylthiolation reactions is summarized, and the related mechanism are also discussed.

Indolines, an important class of heterocycles with a wide range of biological properties, are a key structural motif in numerous natural products and biologically active compounds. As a result, efficient methods for indolines synthesis have been the subject of extensive studies. In this review, recent studies on the synthesis of various functionalized indolines using unactivated alkenes are described. It involves radical addition/cyclization reaction in the presence of oxidizing agent, which is usually carried out under neutral reaction conditions using readily available oxidizing agents and different transition metals or under metal-free as catalysts.

Development of efficient and practical asymmetric catalytic reactions plays a pivotal role for the concise syntheses of chiral drugs. Chiral ligands and catalysts are crucial for the selectivity and reactivity of the catalytic reactions. In this account, the design and development of a series of P-chiral mono- and bis-phosphorus ligands were summarized based on a benzooxaphosphane backbone and their applications in the synthesis of chiral drugs. Beside their P-chirality, these ligands are structurally rigid, sterically bulky, and electron-rich, providing good physical properties and tunabilities. Facilitated by these chiral ligands, a series of efficient and practical reactions including asymmetric hydrogenation, asymmetric cross-coupling, asymmetric cyclization, and asymmetric nucleophilic additions have been developed. The excellent conversions, yields, regioselectivities, enantioselectivities, and broad substrate scope have enabled concise and efficient syntheses of a series of chiral drugs.

Maleimide, a common motif in a variety of natural alkaloids, has been extensively investigated due to its noteworthy biological activities and optical properties. Additionally, it can be transformed into many important heterocyclic frameworks such as succinimides, pyrrolidines, and 2-pyrrolidones. Thus, a great deal of attention has been focused on the development of new synthetic routes to access polyfunctionalized maleimides. In this article, the recent research progress in functionalization of double bond is reviewed based on maleimides according to Michael addition, oxidative coupling and cycloaddition reaction.

Optically pure 1,3-amino alcohol is not only the important synthon in organic synthesis, but also the core structure of numerous bioactive molecule. As a result, the formation of 1,3-amino alcohols occupies a hot resarch topic in asymmetric synthesis. This review symmarizes several types of frequently-used methods and progress on synthesizing 1,3-amino alcohols:aldol or azo-aldol condensation synthesis, transition metal catalyzed C-H activation and amination synthesis, ring-opening and addition of azocyclic compounds, and[3+2] dipolar-cycloaddition reaction etc.

Water is a medium for reaction in living organisms, which is safe, cheap and easy to obtain, and visible light is a clean and renewable natural resource. Exploring the controllable free radical reaction under the illumination condition in water and developing a simple, green and efficient synthesis method not only conform to the current green chemistry theme, but also have an important scientific significance in theory and practical application. The classification and review of visible light catalysis in aqueous phase have been carried out in recent years, and the corresponding mechanisms are discussed.

The photocatalytic redox reactions have been widely concerned in organic chemistry due to their green, efficiency and safety. In this review, the cross-coupling/aromatization reactions are described based on photocatalytic organic hydrogen-evolution, which can be used to build organic carbon-carbon and carbon-heteroatom bonds by using a photocatalyst/catalyst dual catalytic system. Hydrogen is the only by-product in these reactions. The system and catalytic mechanisms of organic photocatalytic redox reaction are highlighted.