Organocatalytic Asymmetric Michael/Dieckmann Cyclization Reaction …
2019年8月16日 · A highly enantioselective conjugate addition/Dieckmann cyclization of 3-carboxymethyl substituted oxindoles with electron-deficient internal alkynes was achieved under the catalysis of a chiral guanidine catalyst and NaH.
Asymmetric Cycloaddition and Cyclization Reactions Catalyzed …
2017年10月2日 · In this Account, we summarize our recent studies on asymmetric cycloadditions between various dienophiles and dienes, dipoles and dipolarophiles, and cascade cyclizations catalyzed by chiral N, N ′-dioxide–metal complexes.
Recent advances in Pd-catalyzed asymmetric cyclization reactions ...
2023年12月18日 · This review aims to collect the latest advancements in enantioselective palladium-catalyzed cyclization reactions over the past eleven years, and it is organized into thirteen sections depending on the different types of transformations involved.
The Dieckmann Cyclization - Chemistry LibreTexts
Having a carbonyl group in the beta position allows the ester to be removed through decarboxylation. The combination of these three reactions (1) Dieckmann cyclization, (2) alpha alkylation, and (3) decarboxylation provides an efficient method for preparing 2-substituted cyclopentanones and cyclohexanones.
Asymmetric Organocatalytic Cyclization and Cycloaddition Reactions
2011年5月26日 · Organo-Catalyzed Asymmetric Michael–Hemiketalization–Oxa-Pictet–Spengler Cyclization for Bridged and Spiro Heterocyclic Skeletons: Oxocarbenium Ion as a Key Intermediate. Organic Letters 2017 , 19 (24) , 6626-6629.
Asymmetric Catalytic Reactions of Donor–Acceptor Cyclopropanes
2020年7月28日 · Enantioselective reactions of donor–acceptor cyclopropanes are a particularly valuable approach for the production of enantioenriched chiral 1,3-difunctionalized ring-opened systems as well as carbo- and heterocycles. A number of chiral catalysts have been developed for asymmetric ring-openings, annulations, and rearrangements.
Asymmetric Cycloaddition and Cascade Addition–Cyclization Reactions ...
2015年1月1日 · MacMillan and co-workers developed a novel catalytic asymmetric cascade arylation–cyclization reaction of indole-based nucleophiles with diaryliodonium salts using Cu(I)-bisoxazoline catalysis under mild conditions (Scheme 39) . This transformation provides a new and direct strategy for the rapid and highly enantioselective construction of ...
Radicals as Chiral Catalysts for Asymmetric Radical Cyclization Reactions
2024年5月31日 · Herein, we highlight several creative and strategic advances in chiral radical catalyst design, cyclization reaction achievements, and future challenges. In the 1980s, some pioneering studies by Feldman and Oshima revealed that the thiyl radical could catalyze cyclization of vinylcyclopropane with alkenes, providing access to racemic cyclopentanes.
Recent Progress in Asymmetric Domino Intramolecular Cyclization…
2023年7月18日 · This review summarizes the specific conditions, mechanisms and yields of synthesis, as well as the advantages and disadvantages of various methods, and aims to stimulate new ideas and methods for asymmetric domino cyclization/cascade reactions of substituted alkenes in organic synthesis.
Catalytic asymmetric dearomatization (CADA) reactions offer an efficient strategy for directly converting aromatic compounds into chiral cyclic molecules. Cascade dearomative...