Reactions that promote the formation of carbon-carbon bonds are of great importance in organic synthesis, since those transform available, relatively inexpensive, and small organic molecules into the more complex ones. One of the main protocols used for these transformations are cross-coupling reactions, and due to their versatility and applications, several efforts have been devoted recently into

A practical and mild three-component reaction between indoles, quinoxalin-2(1H)-ones, and CF3SO2Na is disclosed for the facile access of various 3-[2-(trifluoromethyl)1H-indol-3-yl]quinoxalin-2(1H)-ones using low-cost and catalytic amount of CuF2 as the catalyst. This strategy includes merits of high site-selectivity, step economy, and broad substrates scope. Synthetic utility was demonstrated by the

A Lewis acid-catalyzed (3+2) cycloaddition of 2-indolylmethanols with β,γ-unsaturated α-ketoesters was established, which afforded a series of cyclopenta[b]indoles in overall high yields (up to 98%) with excellent diastereoselectivities (up to >95:5 dr). This reaction not only represents the first C3-nucleophilic (3+2) cycloaddition of 2-indolylmethanols, but also provides a good example for (2+n)

A calix[4]pyrrole receptor bearing two proximally meso - meso linking isophthaloyl straps displays open and closed states depending on the calix[4]pyrrole conformation. In the crystal structures and in non-polar solvent, the calix[4]pyrrole adopts open 1,3-alternate conformation with straps on the sides. Anion binding triggers a closed state of the receptor providing two types of interactions with

The demand for azobenzenes has exponentially grown due to their wide range of applications in textile, medical, and dye industries. Here we report a procedure to synthesise azobenzenes by the dehydrogenative coupling of anilines in the presence of CoII(TPP) (TPP = dianion of tetraphenyl porphyrin) catalyst and 4‑nitrophenyl azide oxidant species. Differently substituted azobenzenes were obtained in

Unprotected 6,7-benzotropolone and bromine were known to undergo an electrophilic substitution delivering the 7-bromo derivative; it was carried on as its methyl ether. O-Acety l-6,7-benzotropolone added bromine at the C 8 =C 9 bond whereupon an amine-induced E1 cb elimination led to the 8-brominated benzotropolone acetate; ester cleavage with aqueous acetic acid and etherification with diazomethane

This work provides a switchable strategy to access, via a Nazarov cyclization, two diastereomeric disubstituted 3,4,5,6-tetrahydrocyclopenta[ b ]pyran-7(2H)-ones from an activated dienone bearing a chiral sulfoxide. The switch in the torquoselectivity is controlled by the nature of the Lewis acid used as promoter. From the four possible stereoisomers, only the two trans were observed. The Lewis acids

A simple electrochemical protocol is established for the selective alkene dibromination of naturally derived olefins, such as terpenes. The use of hazardous Br 2 or its analogues have been elegantly avoided by employing readily available, inexpensive and harmless sodium bromide with a dual role as reagent and supporting electrolyte in combination with sustainable carbon-based electrodes. This electrochemical

A photoinduced acylation/arylation of N -(arylsulfonyl)acrylamide with acyl oxime esters through a nitrogen-centered radical protocol has been disclosed for the preparation of functionalized indolin-2-ones, which proceeds through a cascade acyl radical addition of carbon-carbon double bond, aryl migration, desulfonylation, and intramolecular cyclization sequence. This redox-neutral strategy features

The deployment of multicomponent reactions (MCRs), defined as containing three or more reactants, not only enjoys pot, atom, and step-economy in the synthesis of novel complex molecules but also aligns with sustainable chemistry principles as a green symphony. Generally, more components lead to more complexity, and are taken to an extreme ‘‘higher-order’’ MCRs, where six or even more components react

Functionalization of an unactivated C-H bonds is a highly desirable process in organic chemistry as it gives direct access to many new functional groups in a single step. This process is generally achieved using transition metal catalysts and among the transition metals studied for C-H activation, palladium plays an important role due to its unique reactivity. Photoredox catalysis has witnessed a huge

Photochemical, sigmatropic 1,3-acyl shifts represent a powerful tool to construct quaternary carbon atoms and the backbones of complex natural products which cannot be constructed easily by conventional methods. This review highlights applications of 1,3-acyl shifts to elegant, partly biomimetic total syntheses of natural products by discussing the underlying photochemical equilibrium.

Attempts to synthesize fluorosulfonyl-substituted pyrazolines by Huisgen reactions (1,3-dipolar cycloadditions) of dimethyl diazomalonate with ethenesulfonyl fluoride led to the formation of dimethyl (2R*,3S*,4R*)-2-(1,3-dimethoxy-1,3-dioxopropan-2-yl)-3-(fluorosulfonyl)-4-((fluorosulfonyl)methyl)cyclo­butane-1,1-dicarboxylate, a highly substituted cyclobutane derivative, which was characterized by

The development of novel and effective metal-free catalytic systems, which can drive value-added organic transformations in environmentally benign solvents (for instance, water), is highly desirable. Moreover, these new catalysts need to be harmless, easy-to-prepare, and potentially recyclable. In this context, amine-rich carbon dots (CDs) have recently emerged as promising nano-catalytic platforms

The synthesis and characterization of a small series of cyclic triimidazole derivatives functionalized with methylated pyridines or guanidines moieties is reported. These compounds were tested for their ability to bind to G-quadruplexes from both telomeric and oncogene promoter sequences. Some of them exhibited high affinity and effective G-quadruplex-stabilizing properties. Overall, these compounds

The energies of CH2=CH–CH=NR2 + + HNR*2 = CH2=CH–CH=NR*2 + + HNR2 reactions (exchange of propenal between two secondary amines) and of similar equilibria with cinnamaldehyde have been calculated and compared. Iminium ions from pyrrolidines with substituents that can help stabilize the positive charge are especially stable in the gas phase, as expected, whereas in very polar solvents the predicted order

An eco-friendly metal-free protocol was developed for the regioselective synthesis of densely functionalized 1,2,3-triazoles via a 1,3-dipolar cycloaddition reaction of alkanone enolates with azides performed in the environmentally responsible choline chloride/urea or choline acetate/urea eutectic mixture. This approach displays a broad substrate scope, straightforwardly furnishing the desired triazoles

Bis(pyrazolyl)borate complexes [BBN(pz R ) 2 ]Cu(I) were evaluated as catalysts in the reaction of carbene/nitrene transfer and addition to C=C bonds of a wide range of aromatic, heterocyclic and aliphatic olefins. The complexes exhibit high catalytic efficiency and selectivity in both processes.

The Tsuji-Trost reaction of cyclopentenyl carbonates was explored by experimental studies and computational calculations, in search for the synthetic conditions enabing the stereoconvergent synthesis of cyclopentenyl nucleosides. Under common conditions, cyclopentenyl reagents provide Tsuji-Trost products only in a weakly stereoconvergent manner. However, changes in the amount of catalyst (up to 1

A practical protocol for the synthesis of ketones by Pd-catalyzed cross-coupling of phenol derivatives with nitroalkanes followed by a Nef-type reaction has been developed. The readily available nitroalkanes served as alkyl nucleophiles under basic conditions to couple with easy-to-handle phenol derivatives derived from naturally abundant phenols. The avoidance of using organometallics and organic

6-methylquinazolin-4(3H)-one-based compounds were here identified and synthesized as novel binders of bromodomain-containing protein 9 (BRD9) epigenetic reader. Accounting a fast and efficient synthetic route aimed to easily obtain differently 2- and 8-disubstituted 6-methylquinazolin-4(3H)-one derivatives, a virtual library of synthesizable items was built and submitted to molecular docking experiments

A convenient and efficient method for one pot synthesis of polysubstituted (Z)-halobenzo[c,d]indoles from 8-alkynyl-1-naphthylamine derivatives using CuCl2 and CuBr2 as the halogenated reagents has been developed. In this protocol, both (Z)-chloro and bromobenzo[c,d] indole derivatives can be obtained in moderate to good yields by copper halide-promoted stereoselective intramolecular cis-addition annulation

The KI/TBHP (tert-butyl hydroperoxide) promoted [3+2] annulation between dibenzo[b,f][1,4]oxazepine-imines (DBO-Imines) and N-tosylhydrazones under mild conditions has been developed, affording a direct and high atom-economical preparation for tetracyclic 1,2,4-triazoline-fused dibenzo[b,f][1,4]oxazepines (DBOs) in good to excellent yields. This procedure could tolerate a wide range of functional groups

Base-promoted formal [4+2] cycloaddition reaction of ( Z )-2-(2-hydroxy-2-alkylvinyl)quinoline-3-carbaldehydes and allenoates represents an efficient method for the synthesis of functionalized acridines via a sequential Michael addition, aldol condensation, and isomerization process in a mild condition. This new approach tolerates a wide range of ( Z )-2-(2-hydroxy-2-alkylvinyl)quinoline-3-carbaldehydes

Functionalized 4,4-difluorospiro[2.2]pentan-1-yl derivatives are proposed as promising building blocks for synthetic and medicinal chemistry. Scalable, efficient, and diastereoselective approach to their preparation via the difluorocyclopropanation of (2-methylene­cyclopropyl)methanol is developed. Stability of the title scaffolds towards common reaction conditions is confirmed by a series of typical

A series of readily regenerable thioimidazolium-based ionic liquids possessing the ability to transfer an alkyl group to a nucleophile are immobilized on crosslinked polystyrene beads. Different alkyl groups can be loaded onto the resin, highlighting the tunability of the material. The efficiency of these materials is demonstrated by their screening against a series of nucleophiles, showing a particular

The article presents an in-depth study of the applicability of cooperative [M]-/Organo-catalytic systems in aerobic Si–H-functionalization. A thorough kinetic study allowed us to identify two “complementary” catalytic systems based on earth-abundant [M]-catalysts and inexpensive commercially available organic catalysts. The first system, Co(OAc) 2 /N-hydroxysuccinimide, made it possible to oxidize

Isophlorins (two-electron-reduced porphyrins) with 20π antiaromaticity have been synthesized by metallation or core modification (replacing the inner NHs with less bulky atoms) thus far. The core-modification number (CMN) is an important factor for the stability of isophlorins against their oxidation to porphyrins. However, isophlorins with small CMN (≤ 2), i.e., without significant core modification

Aluminium is the most abundant metal in the earth crust and so far, there is no evidence on an important role on the human body and it is well known the relation aluminium exposure on human health and aluminium-related diseases. The aim of this review is to attempt to know the most recent advances on multidentate organic compounds such as naphthalene, coumarin, quinoline, Schiff bases, benzothiazole

A low transition temperature mixture formed with 1-butyl-3-(methoxycarbonylmethyl)imidazolium chloride and iron(III) chloride has proven to be an efficient catalyst for the synthesis of quinazolines following a sequence of condensation-cyclization-oxidation reactions. The protocol is simple and effective for coupling 2-acylanilines and benzylamines to form nitrogen containing heterocycles with moderate

Since their discovery, polyhydroxylated indolizidines have been the focus of attention for both biologists and synthetic chemists. They are classified as iminosugar alkaloids: nitrogen-based carbohydrate mimetics that are potent inhibitors of glycosidases. Many discovered glycosidase inhibitors were found to possess biological activity, and they are therefore considered to be potential therapeutics

The direct regioselective C-H-functionalization of simple, unfunctionalized pyridines is considered a long-standing challenge in heterocyclic chemistry. Herein, we report a novel one-pot protocol for the C4-selective sulfonylation of pyridines via triflic anhydride (Tf2O) activation, base-mediated addition of a sulfinic acid salt and subsequent elimination/rearomatization. Contrary to previous approaches

The replacement of the disulfide bridge by other types of side chain linkages has been a continuous endeavor in the development of cyclic peptide drugs with improved metabolic stability. Octreotide is a potent and selective somatostatin analog that has been used as an anticancer agent, in radiolabeled conjugates for the localization of tumors and as targeting moiety in peptide-drug conjugates. Here

Further hydrolysis of an open-cage fullerene derivative with an epoxy moiety on the rim of the orifice led to the formation of a new open-cage fullerene with a 17-membered orifice and an amide group directly above the orifice. The water encapsulation ratio in the new open-cage compound reached 100% as a result of heating with water at 80 O C. The amide group above the orifice completely blocks the

Asymmetric cycloaddition/annulation reactions have contributed greatly to the synthesis of a variety of novel cyclic compounds used in organic synthesis, natural product synthesis, material science, and chemical biology. Thus, chiral phosphoric acid-catalyzed asymmetric cycloaddition reactions have received the attention of synthetic community to design new vital asymmetric reactions and synthesize

Herein, an method for N -aryl amides preparation has been established via Rh(III)-catalyzed C(sp 2 )- N cross-coupling reactions of alkyl dioxazolones with arylboronic acids, heterocyclic boronic acid, and alkenyl boronic acid. This efficient and straightforward catalytic approach was featured with broad substrate scope (38 examples), good functional group compatibility, high yields (up to 99%) and

Benzothiazinones are a structural motif found in biologically active compounds, such as the clinical candidates BTZ-043 and Macozinone for the treatment of tuberculosis. We describe a robust, two-step method to synthesize 2-amino-substituted benzothiazinones from benzoyl thiocarbamates, which were prepared in a one-pot procedure from benzoyl chlorides. The intramolecular cyclization and ethoxy displacement

Furfural and related compounds are building blocks of industrial interest, obtained from renewable raw biomasses containing C5- and C6-monosaccharides. In recent years, their use as precursors of basic and fine chemicals has gained increasing attention as a green alternative to petroleum-derived compounds. Several works have reported the functionalization of furfurals to obtain a wider range of chemicals

Organic azides have found wide application in various fields of science and technology. This review summarizes recently developed approaches to the direct, one-step synthesis of diverse organic azides utilizing hypervalent iodine reagents. The first part of review deals with the azidation using unstable azidoiodinanes generated in situ from common hypervalent iodine reagents (such as diacetoxyiodobenzene

A rhodium-catalyzed oxidative cross coupling/annulation of indole carboxylic acids with unsymmetric internal trifluoromethylated alkynes was accomplished for direct access to diverse trifluoromethylated indolopyranones, which combined indole, pyranone and trifluoromethyl, three valid pharmacophores, into one molecule. Both indole-3-carboxylic acids and indole-2-carboxylic acids proved to be suitable

Organolithium reagents are one of the most widely used reagents in chemical synthesis. Herein, we reported the first study of organolithium reagents used in asymmetric allylic alkylation (AAA) reactions with racemic cyclic substrates. A simple and efficient Cu-catalyzed synthesis of enantiomerically enriched cycloalkene derivatives from various racemic cyclic allylic bromides was developed. The standard

A series of L-lyxo and L-xylo- pentofuranose-mimetic iminosugars and derivatives were efficiently synthesized in a stereoselective manner, through a concise strategy which involves an organocatalyzed Mannich reaction of an imine and a protected dioxanone as key step, using D-proline as catalyst. A prelimiary evaluation of their activity as potential anti-trypanosomal agents was studied. One of the

An efficient synthesis of functionalized alkynyl phosphine oxides is described. The current approach is based on the activation of the phosphorus–hydrogen bond (P–H bond) of a secondary phosphine oxide. After the deprotonation step using n -butyllithium, the in-situ generated LiP(O)RR’ undergoes further condensation with a wide variety of electrophiles, and without a cyclisation step into the alkyne

A simple and efficient synthetic method to structure C–S bonds was established based on Chan-Lam reaction. A series of O/N -alkyl S -phenyl phenylcarbamothioates were obtained in good yields by using odorless O/N -alkyl phenylthiocarbamates as sulfur sources and commercially available phenylboronic acids as substrates catalyzed by Cu(OAc) 2 . This methodology features simple performance, odorless sulfur

PhI(OAc) 2 /CuI-promoted ring rearrangement of 1,3-azasilinyl-4-epoxides has been developed. The reaction proceeds by a Si-C bond migration/oxidation process, leading to structurally novel 2-silamorpolines containing an aryl/aldehyde groups-substituted quaternary carbon.

Halogens play a crucial part in synthetic organic chemistry. The excellent electrophilicity properties and the leaving group abilities are responsible for the activation and structural derivation of various organic compounds. The cyclization reactions in the presence of halogens allow the researchers to construct diverse carbocycles and heterocycles. The halogen-induced cyclization reactions work very