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Main observation and conclusion: The [8+4] cycloaddition of indene‐2‐carbaldehydes with indole‐2,3‐quinodimethanes and pyrrolidone‐3,4‐dienes is described, affording indole and pyrrolidone annulated bicyclo[4.2.1]nonanes in a highly peri‐, diastereo‐, and enantioselective fashion in the presence of a secondary amine catalyst. This reaction, which proceeds through catalytically generated isobenzofulvenes, represents the first asymmetric version of high‐order [8+4] cycloaddition. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: A palladium‐catalyzed asymmetric [4 + 3] cycloaddition of trimethylenemethanes and indoline‐derived aza‐dienes has been developed. The potential [3 + 2] side pathway was completely suppressed in the process. This protocol provides an efficient access to azepino[2,3‐b]indoles bearing two vicinal stereocenters in generally excellent diastereo‐ and enantioselectivities (up to > 20 : 1 dr, 99% ee). [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: A palladium‐catalyzed asymmetric [4 + 3] cycloaddition of trimethylenemethanes and indoline‐derived aza‐dienes has been developed. The potential [3 + 2] side pathway was completely suppressed in the process. This protocol provides an efficient access to azepino[2,3‐b]indoles bearing two vicinal stereocenters in generally excellent diastereo‐ and enantioselectivities (up to > 20 : 1 dr, 99% ee). [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: The catalytic asymmetric 1,3‐dipolar [3 + 2] cycloaddition of azomethine ylides with stilbenes has been established, affording structurally diverse pyrrolidines bearing four contiguous stereocenters with stereo‐diversity in generally high yields and good to excellent stereoselectivities (up to 98% yield, 99 : 1 dr, >99% ee). Meanwhile, this strategy allowed the formal synthesis of antitumor drug RG7388 (Phase III clinical study) and its analogues in high efficiency. [ABSTRACT FROM AUTHOR]

An efficient catalytic asymmetric 1,3-dipolar cycloaddition of azomethine ylides with four-membered ring-containing exocyclic alkenes has been developed, and either the exo or endo spirocyclic pyrrolidine-azetidine/oxe(thie)tane derivatives were diastereodivergently generated by employing Cu(i)/tBu-Phosferrox and a Cu(i)/N,O–ligand complex, respectively. Notably, various heteroatom-containing (N, O, S) exocyclic alkenes were found to be well-tolerated in this transformation. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: The catalytic asymmetric [3+2] cycloaddition of α‐ketoesters with 2‐nitrovinylindoles and 2‐nitrovinyl‐ pyrroles has been established. This strategy allowed the construction of structurally diverse pyrrolo[1,2‐a]indoles bearing three contiguous stereocenters in generally high yields and good to excellent stereoselectivities (up to 98% yield, > 98 : 2 dr, 99% ee). The efficient synthesis of tetracyclic psychotropic compound analogue via the derivatization of cycloadduct showed the great synthetic potential of this strategy. Nickel(II)‐catalyzed asymmetric [3+2] cycloaddition of α‐ketoesters with 2‐nitrovinylindoles was established, affording pyrrolo[1,2‐a]indoles bearing three stereocenters in high yields and stereoselectivities. [ABSTRACT FROM AUTHOR]

An organocatalytic asymmetric formal aza‐[3+3]cycloaddition of readily available N‐Tosyl‐3‐aminobenzofuran with α,β‐unsaturated aldehydes was developed for the first time. This method enables the facile synthesis of biologically active and synthetically challenging polysubstituted fused benzofuran derivatives bearing two stereocenters in high yields with excellent diastereo‐, and enantioselectivity (up to >20 : 1 dr, and >99% ee). [ABSTRACT FROM AUTHOR]

Palladium-catalyzed [5 + 2] cycloaddition of 2-aryl-2-vinyloxiranes with sulfamate-derived cyclic imines is described. The zwitterionic allylpalladium intermediates act as five-membered synthon to react with sulfamate-derived cyclic imines to furnish [5 + 2] cycloaddition, giving 1,3-oxazepine derivatives in moderate to excellent yields with excellent regioselectivities. [ABSTRACT FROM AUTHOR]

Conjugated alternative donor–acceptor type pyrrol-pyridazyl-triazolyl-pyridineN-heterocyclic systems were synthesized via Cu(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition reaction of pyrrol-pyridazylacetylene with azidopyridines. [ABSTRACT FROM AUTHOR]

A highly efficient asymmetric 1,3-dipolar cycloaddition of azomethine ylides to α-alkylidene succinimides catalyzed by a novel chiral N,O-ligand/Cu(OAc)2 system is reported, affording dispiropyrrolidine derivatives with spiro quaternary stereogenic centers in good to excellent yields (up to 90%), excellent levels of diastereoselectivities (＞20 : 1 dr) and enantioselectivities (up to 97% ee). [ABSTRACT FROM AUTHOR]

[Display omitted] Post-synthetic modification is an important strategy for improving and enhancing the properties and functions of covalent organic frameworks (COFs). Two imine-linked COFs are converted into the quinolone-linked COFs by converting the dynamic imine linkages in the COFs into more robust quinolone ring via aza-Diels-Alder cycloaddition reaction. The prepared quinolone-linked COFs not only maintain good crystallinity and porosity, but also possess expanded conjugate planes, enhanced light absorption and excellent stability. The quinolone-linked COFs present remarkable performance of photocatalytic oxidation reactions, including oxidation of phenylboric acids, coupling of benzylamine, and oxidation of thioethers. This work is helpful for preparing organic porous photocatalytic materials with high performance and long life. [ABSTRACT FROM AUTHOR]

The article presents the synthesis of pyrrol-pyridazyl-triazolyl-pyridines via Cu(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition reaction, and describes its chemical reaction.

The Cu-catalyzed 1,3-dipolar cycloaddition of 5-alkylidene thiazolidinediones with azomethine ylides generates a variety of chiral spirocyclic pyrrolidine-thiazolidinediones (III), (V), and (VII). [ABSTRACT FROM AUTHOR]

A series of chiral dispiropyrrolidines (III), (V), and (VII) is readily prepared by a copper-catalyzed 1,3-dipolar cycloaddition of azomethine ylides (II) and (IV) to α-alkylidene succinimides (I) and (VI), respectively. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed enantioselective [4 + 2] cycloaddition reaction of vinyl benzoxazinones with sulfamate-derived cyclic imines is described, affording the tetrahydroquinazolines bearing several functional rings in high yields (up to 99% yield) with good to excellent diastereoselectivities and excellent enantioselectivities (up to 96% ee). This reaction represents the first Pd-catalyzed asymmetric decarboxylative cycloaddition of vinyl benzoxazinones with imines. [ABSTRACT FROM AUTHOR]

TheSc(OTf)3-catalyzed diastereoselective [3 + 3] cycloadditionof phthalaziniumdicyanomethanides with cyclopropane 1,1-diesters proceeded smoothlyunder mild reaction conditions, affording a variety of 3,4-dihydro-1H-pyrido[2,1-a]phthalazine derivativesin up to 99% yields with excellent diastereoselectivities. [ABSTRACT FROM AUTHOR]

Among various chiral N,O-ligands tested, the 7-chloro derivative CQI is found to be the optimal one. [ABSTRACT FROM AUTHOR]