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An NBS-induced intramolecular annulation of 3-(1H-indol-3-yl)-propanamide is described. The C2-substituents on indole ring have great influence upon the generation of fused- and spirocyclic indolines.

An efficient Mn(iii)-promoted cascade reaction of tryptamine-derived isocyanides with arylboronic acids for accessing spiroindoline derivatives is described.

Herein, a novel chelation-assisted C-H arylation reaction of benzo[h]quinoline is described. This transformation, using [RuCl

A palladium-catalyzed three-component reaction of isocyanides, 2,2,2-trifluoro

Herein, a novel visible-light photocatalytic radical addition-translocation-cyclization (RATC) approach for the efficient synthesis of sulfonyl-containing azacycles is described. The reaction delivers a wide range of monocyclic, bicyclic and polycyclic azacycles by using easily prepared sodium sulfinates and

1,10-Phenanthroline-assisted, Ni(ii)-catalyzed para-carboxylation of phenol derivatives is reported.

A novel and green multicomponent reaction in aqueous media is developed for the efficient synthesis of 1,3-selenazolines.

A divergent reaction of isocyanides with o-bromobenzaldehydes for the synthesis of isoindolinone-derived ketenimines and lactams was disclosed. The reaction features readily available reactants, relatively mild conditions, and high yields of products. Ketenimines could be applied in further transformations for access to other functional molecules. A mechanism study showed that the palladium-migration/imine-insertion process was the key step in this reaction.

Herein, a novel palladium-catalyzed regioselective diarylation/deamination of homoallylamines is described. During the process, a ubiquitous free amine (NH

Novel and efficient Mn(OAc)3⋅2H2O promoted radical addition-[4 + 1] cyclization relay of 3-indolymethanols and phosphites was disclosed, which afforded 1,2-oxaphospholoindole derivatives in moderate to good yields. Based on the experimental and computational studies, a mechanism involving radical addition and intramolecular cyclization cascade was proposed.

An atom- and step-economical strategy for the synthesis of bisphosphinoylaminomethanes is reported. This metal-free bisphosphinylation reaction proceeded smoothly through a base-mediated direct 1,1-bisphosphonation of phosphine oxides and isocyanides under mild conditions. The present method offers a facile, efficient, and general approach to a broad range of bisphosphinoylaminomethane derivatives in moderate to good yields.

In many reactions involving selenosulfonate or thiosulfonate, the sulfone group often leaves in form of benzenesulfinic acid or sodium benzenesulfinate. A one-pot two-step reaction of selenosulfonate with isocyanides and allyl alcohol under aqueous conditions to afford selenocarbamates and allyl sulfone compounds is reported. The sulfinic acid as the first-step side product is converted to the allyl sulfone compound by water promoted reaction with allyl alcohol. Water acts as both an oxygen source of selenocarbamates and as a promoter to drive the second step reaction. The reactions have the advantages of mild conditions, green, environment-friendly, and high atomic economy.

A Co-catalyzed coupling of 3-(2-isocyanoethyl)indoles with organic azides in pure water for accessing spiroindolenine derivatives was developed. This strategy features mild reaction conditions, high atom-economy, excellent yields, wide substrate scopes, and broad functional group tolerance. The products were obtained simply by sequential operation involving extraction, concentration, precipitation, and filtration, without tedious column chromatography. More importantly, the aqueous catalytic system could be recycled at least ten times without reducing the catalytic activity. The strategy provides a green and efficient method for the construction of spiroindolenine derivatives.

Herein, we present a Mizoroki–Heck reaction initiated formal C(sp3)–H arylation of α-methylcinnamaldehydes. The reaction proceeds smoothly under phosphane-free conditions, and provides a facile method to access important α-methylcinnamaldehyde derivatives with good functional groups tolerance and good stereoselectivity. The obtained product is further converted into a substituted allylic alcohol and diene easily.

A Mn(III) mediated radical reaction of new designed multi-functionalized 2-isocyano-6-alkenyl(alkynyl)benzonitriles with arylboronic acids has been developed. This reaction provides a method for the synthesis of pyrroloisoquinoline derivatives through the formation of two C C bonds and one C N bond via radical cascade cyclization in one step.

An atom- and step-economic multi-component cobalt-catalyzed synthesis of amidines has been reported by using amines, isocyanides, and diazo compounds as carbene sources. This protocol provides a synthetically simple, highly efficient strategy for the straightforward synthesis of functionalized amidines with a range of substrates.

An efficient synthesis of 3-(diarylallylidene)oxindoles from 3-(1H-indol-3-yl)-1,1-diarylpropan-1-ol under metal-free conditions is described. NBS serves as a critical medium leading to a facile oxygen-migration in the transformation. The protocol has advantages of high efficiency, simple opreation, mild reaction conditions, good atom-economy, wide substrate scope and good yields of products. A detailed mechanism is proposed after careful investigation.

A rhodium-catalyzed synthesis of indoloquinazolinone from a readily available hypervalent iodonium reagent and N-carboxamide indole was developed. The protocol features broad functional group tolerance, mild conditions, and excellent yields. The target products were obtained simply by filtration, without tedious column chromatography. Notably, the noble metal catalyst system can be recycled effectively at least ten times. The strategy may be amenable to industrial production.

Direct functionalization of a C-H bond at either the meta or para position by only changing the catalyst system poses a significant challenge. We herein report the [Fe(TPP)Cl]-enabled, selective, C-H difluoromethylation of arenes using BrCF2CO2Et as the difluoromethylation source, which successfully altered the selectivity from the meta to the para position. A preliminary mechanistic study revealed the iron porphyrin complex not only activated the aromatic ring but also induced para selectivity due to the influence of ligand sterics.

It has always been a challenge in free radical chemistry to control site selectivity during the reaction of free radicals with aromatic rings. Herein, we report the site-selective carboxylation of anisoles through the direct reaction of the bromoform radical with a benzene ring at the

An efficient cascade reaction of tryptamine-derived isocyanides with C,N-cyclic azomethine imines is described. The polycyclic pyrrolo[2,3- c ]quinoline derivatives, which benefited from rearrangement process driven by hydrogen bonding, could be directly assembled in moderate to good yields (40-87%) under metal-free and mild conditions. This transformation involved four new heterocyclic rings formations and uniquely, ring opening of indole as well as ring expansion of C,N-cyclic azomethine imine. Both experimental and DFT studies provided guidance on the in-depth insight into the reaction pathways and hydrogen bonding was identified to lower the free energy barrier in transition states. This work constitutes a rare example of tryptamine-derived isocyanide-based cascade reactions, and potentially could be a powerful synthetic strategy for accessing polycyclic analogues involved in natural products.

A TFA promoted multi-component reaction of aryldiazonium with sodium metabisulphite and thiols to construct thiosulfonates under transition-metal free conditions is reported. The thiosulfonates were isolated in good yields with broad tolerance of functional group. Readily available inorganic Na2S2O5 was applied as the sulfur dioxide surrogate. This strategy features easily available substrates, mild reaction conditions and free transition-metal catalyst.

In this paper, a visible-light-promoted cross-coupling of 4-alkyl-1,4-dihydropyridines with thio-/selenium sulfonates under transition-metal-free conditions is described. This strategy features easily available substrates, mild reaction conditions, high yields, and high chemoselectivity. A novel synthetic route for the construction of a sulfide or selenide C

This report describes the synthesis of organoselenyl isoquinolinium imides through a tandem cyclization between N'-(2-alkynylbenzylidene)hydrazides and diselenides. The reaction was carried out at room temperature under an ambient atmosphere using cheap iron(iii) chloride as the metallic source. The strategy shows good tolerance to a broad range of N'-(2-alkynylbenzylidene)hydrazides and diselenides, and forms C-N and C-Se bonds in one step. The obtained product is further transformed into a bioactive H-pyrazolo[5,1-a]isoquinoline skeleton easily via a silver catalyzed [3 + 2] cycloaddition.

In this paper, synthesis of polysubstituted maleimides was described via cascade reaction of isocyanides and α-diazoketones. This strategy features readily available substrates, high atom-economy and metal-free conditions. A variety of valuable polysubstituted maleimides are assembled in good yields.

ObjectiveTo investigate the correlation between intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) and the pathological classification of idiopathic orbital inflammatory pseudotumors (IOIPs).MethodsNineteen patients who were diagnosed with IOIPs (a total of 24 affected eyes) between November 2018 and December 2020 were included in the study. All the patients underwent magnetic resonance imaging orbital plain scans and IVIM-DWI multiparameter scans before an operation. The true diffusion coefficient (D), pseudodiffusion coefficient (D*), and perfusion fraction (f) values were obtained. Based on histopathology, the lesions were divided into three types: lymphocytic infiltration, fibrosclerotic, and mixed. The correlation between IVIM-DWI parameters and pathological classification was tested with the histopathological results as the gold standard. The data were analyzed using SPSS version 17.0, with P < 0.05 defined as significant.ResultsAmong the 19 patients (24 eyes) affected by IOIP, there were no significant differences between IOIP pathological classification and gender or age (P > 0.05). There were statistically significant differences between the D and f values for different pathological types of IOIP and IVIM parameters (P < 0.05), and there was no significant difference in D* value between the different pathological types (P > 0.05).ConclusionThe D and f values showed correlation with different types of IOIP, and the sensitivity of the D value was higher than that of the f value. The D* value showed no significant distinction between pathological types of IOIP.

Herein, a novel sequential ring opening reaction of aza-cyclobutanone oxime esters with isocyanides is described. The reaction proceeded smoothly under redox-neutral and mild conditions, leading to a divergent synthesis of α-cyanomethylaminoamides, α-acyloxyamides and α-acylaminoamides. In these transformations, a selective N–O/C–C or N–O/C–C/C–N cleavage was achieved only by changing the iron-catalyst system. Among them, a rare sequential N–O/C–C/C–N cleavage process with a classical Passerini or Ugi multicomponent reaction can be executed in a single step. To the best of our knowledge, this work creates a novel reaction mode of cycloketone oximes and provides new opportunities for reaction design.

A divergent reaction of isocyanides with

Herein, we present a novel intermolecular radical addition/cyclization and Se-group transfer reaction of terminal alkynes and unsaturated alkyl selenide. The present strategy offers a straightforward, and facile approach for the synthesis of valuable Se-containing cyclopentenes. The remarkable features of this strategy include easily accessible starting materials, metal-free and peroxide-free conditions, high atom economy, simple operation and broad substrate scope. More importantly, the reaction is easy to scale-up and can be extended to the construction of six-membered carbon ring.

A one-step cascade reaction of tryptamine-derived isocyanides with in situ generated nitrile oxides for the synthesis of fused spiroindolines was described. The desired products could be efficiently synthesized in moderate to good yields (42-87%). The protocol features mild conditions, wide substrate scope, and high efficiency.

A Co-catalyzed cyclization reaction of isocyanides, azides, and amines to access quinazoline derivatives was described. This protocol features a high atom economy, mild reaction conditions, excellent yields, and a broad substrate scope. This cascade reaction involved three or four C-N bonds and the formation of one or two rings. The quinazolin-4(H)-imines obtained are proven to be versatile intermediates for further valuable transformations. It was also found that the cobalt catalyst could be isolated from the reaction mixture and reused.

Herein, we present a novel silver- or copper-mediated direct amidation-ketonization-selenation of terminal alkynes for the synthesis of α-oxo-selenoamides. The reaction utilized easily accessible elemental selenium as the source of selenium. In addition, the 18O labeling experiment revealed that TEMPO is the oxygen source of the carbonyl group. The reaction takes advantage of an unsaturated C≡C bond to construct new C═O, C═Se, and C-N bonds in one step.

A visible light-induced Co- or Cu-catalyzed selenosulfonylation of alkynes for the synthesis of β-(seleno)vinyl sulfones is demonstrated. This method utilizes a low-cost cobalt salt or metal copper as the catalysts. The reaction goes through a photoinduced free radical addition of selenosulfonates to alkynes for the 1,2-selenosulfonylation of alkynes under mild conditions.

The simple inorganic rhodium salt RhCl3·3H2O was used as a catalyst to achieve the thiolation of acrylic acids, with a series of (Z)-alkenyl sulfides being obtained exclusively. It is noteworthy th...

A nickel-catalyzed defluorinative reductive cross-coupling of gem-difluoroalkenes with thiosulfonate or selenosulfonates is described. The reaction involves the formation of thiolated or selenylated monofluoroolefins via regioselective C-F bond cleavage and C-S or C-Se bond formation and features easily available substrates, mild reaction conditions, and high E-selectivity. One of the derivatives by further cross coupling with PhMgBr exhibited an aggregation-induced emission enhancement effect.

A palladium catalyzed insert reaction of isocyanides to 3-arylisoxazol-5(4H)-ones for the construction of 4-aminomethylidene isoxazolone derivates is reported. In this transformation, only the C–H ...