Enantioselective Vinylogous Reactions of 3-Alkylidene Oxindoles

Abstract

Oxindoles represent an important class of bioactive compounds and synthetic derivatives found in many natural products. Most of these compounds are chiral molecules and the challenge of their asymmetric synthesis has fascinated many research groups. In particular, the creation of chiral centers out of the oxindole ring by vinylogous addition to 3-alkylidene-substituted oxindoles (3-alkylidene-1,3-dihydro-2H-indol-2-ones) has emerged in recent years. This review aims to give an overview of this topic.1 Introduction2 Aldol and Mannich Reactions3 Addition to Unsaturated Carbonyl Compounds4 Addition to Nitroalkenes5 Miscellaneous6 Conclusion

New Developments of the Principle of Vinylogy as Applied to π-Extended Enolate-Type Donor Systems

“…During the 2010–2018 period considered here, a considerable number of authoritative reviews, accounts, and highlights appeared in the literature that focused on particular aspects of vinylogy . Many of them accounted for specific HOMO-raising catalytic activation modalities of pronucleophiles (amino-organocatalysis, − NHC-organocatalysis, , noncovalent organocatalysis); − some dealt with selected classes of vinylogous functional groups (aldehydes, , nitriles, , alkylidene carbo- or heterocycles , ), while others were focused on either specific reaction types (Michael additions, , Mukaiyama-type C–C bond forming reactions, organocascade reactions) or selected target categories (polyketides, γ-butenolides , ).…”

Expeditious entry into carbocyclic and heterocyclic spirooxindoles

“…In an effort to disclose the methods to synthesize chiral oxindoles, an enantioselective vinylogous reaction of 3-alkylidene oxindoles was reviewed by Dalpozzo and Mancuso. 22 However, it provided an insight into reactions at the periphery rather than the spirocyclic system. We also directed an entry on diastereoselective reactions involving β-monosubstituted and β,β′-disubstituted alkylidene oxindoles affording high levels of facial, regio- and diastereocontrol.…”

The Vinylogous Michael Addition of 3‐Alkylidene‐2‐oxindoles to β,γ‐Unsaturated α‐Keto Esters by Bifunctional Cinchona Alkaloids

“…Over the last few years, research involving catalytic asymmetric direct vinylogous reactions have been growing rapidly A variety of vinylogous pronucleophiles such as butenolides, butyrolactams, coumarins, allyl alkyl/aryl ketones, 5‐alkyl‐4‐nitroisoxazoles, 3‐alkylidene oxindoles, α‐alkyl/arylidene pyrazolinones, 2‐allylazaarenes, β,γ‐unsaturated amides and esters, oxazole‐2‐thiones, N ‐2,2,2‐trifluoroethyl isatin ketimines, enals and enones, nitrones, and α,α‐dicyanoalkenes (Scheme ). have been explored for direct vinylogous Michael reaction.…”