Recent Advances in Catalytic Enantioselective Synthesis of Pyrazolones with a Tetrasubstituted Stereogenic Center at the 4-Position

Pyrazolone [2,4-dihydro-3H-pyrazol-4-one] represents one of the most important five-membered nitrogen heterocycles which is present in numerous pharmaceutical drugs and molecules with biological activity. Recently, many catalytic methodologies for the asymmetric synthesis of chiral pyrazolones have been established with great success, specially, for the synthesis of pyrazolones bearing a tetrasubstituted stereocenter at C-4. This review summarizes these excellent research studies since 2018, including representative examples and some mechanistic pathways explaining the observed stereochemistry

Organocatalytic strategies for the development of the enantioselective inverse-electron-demand hetero-Diels-Alder reaction

Cycloaddition reactions, in particular Diels-Alder reactions, have attracted a lot of attention from organic chemists since they represent one of the most powerful methodologies for the construction of carbon-carbon bonds. In particular, inverse-electron-demand hetero-Diels-Alder reactions have been an important breakthrough for the synthesis of heterocyclic compounds. Among all their variants, the organocatalytic enantioselective version has been widely explored since the asymmetric construction of diversely functionalized scaffolds under reaction conditions encompassed within the green chemistry field is of great interest. In this review, a profound revision on the latest advances on the organocatalytic asymmetric inverse-electron demand hetero-Diels-Alder reaction is shownWe are grateful to the Spanish Government (CTQ2015-64561-R and RTI2018-095038-B-I00), “Comunidad de Madrid” and European Structural Funds (S2018/NMT-4367). J.A.F.-S. thanks the Spanish Government for a Ramón y Cajal contract. V.L.-M. thanks Universidad Autónoma de Madrid for a predoctoral fellowship (FPI-UAM

Asymmetric 1,3-dipolar cycloadditions of acrylamides

This critical review, which is relevant to researchers in synthetic organic chemistry, focuses on asymmetric 1,3-dipolar cycloadditions with acrylamides. The use of chiral acrylamides as dipolarophiles leads to high levels of stereocontrol, due to conformational constraint in the acrylamides. Employment of chiral tertiary acrylamides containing nitrogen heterocycles is particularly effective in controlling the stereoselectivity. Following a general overview of 1,3-dipolar cycloadditions, the main body of the review focuses on asymmetric 1,3-dipolar cycloadditions of acrylamides with nitrile oxides, nitrones, diazoalkanes and azomethine ylides, with particular emphasis on the rationale for the observed stereocontrol (215 references)

The Recent Development of Organofluorine Chemistry in China: Asymmetric Construction of Stereogenic Trifluoromethyl-substituted Carbon Centers

The stereospecific incorporation of the trifluoromethyl group into an organic compound has attracted considerable attention and significant progress has been achieved in the past decade. Scholars from China have also contributed greatly to this field, which is the subject of the current review

Development and application of asymmetric organocatalytic Mukaiyama and vinylogous Mukaiyama-type reactions

This is the peer reviewed version of the following article: "Development and application of asymmetric organocatalytic Mukaiyama and vinylogous Mukaiyama-type reactions", Chemistry - A European Journal 24.43 (2018): 10906-10933 ,which has been published in final form at https://doi.org/10.1002/chem.201801866. This article may be used for non-commercial purposes in accordance with Wiley terms and conditions for use of self-archived versionsOrganocatalysis is a growing area that is benefiting from advances in many fields. Its implementation has begun in areas such as supramolecular chemistry, organic chemistry and natural product synthesis. While a considerable number of important publications in the field of organocatalytic Mukaiyama-type additions have been reported, they are yet to be fully covered in a review. Therefore, we would like to highlight the applications of various kinds of organocatalysts in Mukaiyama-type reactions, while also including the vinylogous Mukaiyama variation. Herein we describe and discuss the development and current state of the art of the organocatalytic Mukaiyama reaction, vinylogous Mukaiyama and related reactionsFinancial support from the Spanish Government CTQ2015-64561-R (MINECO/FEDER) is gratefully acknowledged. M.F. thanks the UAM for an FPI-UAM fellowshi

Recent Advances in Asymmetric Organocatalyzed Conjugate Additions to Nitroalkenes

The asymmetric conjugate addition of carbon and heteroatom nucleophiles to nitroalkenes is a very interesting tool for the construction of highly functionalized synthetic building blocks. Thanks to the rapid development of asymmetric organocatalysis, significant progress has been made during the last years in achieving efficiently this process, concerning chiral organocatalysts, substrates and reaction conditions. This review surveys the advances in asymmetric organocatalytic conjugate addition reactions to α,β-unsaturated nitroalkenes developed between 2013 and early 2017.We thank the financial support from the Spanish Ministerio de Economía, Industria y Competitividad (CTQ2015-66624-P) and the University of Alicante (UAUSTI16-03, AUSTI16-10, VIGROB-173, VIGROB-285)

Asymmetric Addition and Cycloaddition Reactions with Ylidene-Five-Membered Heterocycles

Five-membered heterocycles bearing an exocyclic double bond have been successfully used as substrates in asymmetric addition and cycloaddition reactions. Ylidene-heterocycles are attractive substrates due to their high functionalization and the presence of an electrophilic conjugated exocyclic double bound that can participate in nucleophilic addition reactions as well as cycloaddition reactions, which may be triggered by the formation of aromatic intermediates or products in many cases. During the last decades, catalytic methodologies have been developed using ylidene-heterocycles as substrates in order to synthesize useful optically active heterocyclic derivatives. 4-Ylidene-pyrazol-5-ones, isoxazolin-5-ones, 2,3-dioxopyrrolidines, rhodanines, oxazolidindiones, Erlenmeyer-Ploch azlactones and 5-ylidene-thiazolones have been successfully used as substrates in asymmetric reactions. This review collects the powerful research in asymmetric addition and cycloaddition reactions where ylidene-five-membered heterocycles have been used