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A highly predictive model to correlate the steric and electronic parameters of tertiary amine thiourea catalysts with the stereoselectivity of Michael reactions of 3-substituted benzofuranones and alkyl 2-phthalimidoacrylates is described. As predicted, new 3,5-bis(trifluoromethyl)benzyl- and methyl-substituted tertiary amine thioureas turned out to be highly suitable catalysts for this reaction and enabled the synthesis of enantioenriched α-amino acid derivatives with 1,3-nonadjacent stereogenic centers.

We reported herein a simple and efficient visible-light promoted intermolecular haloamination and haloetherification of alkenes using N-halosaccharin as the halogen and nitrogen/oxygen source (halo = Br, Cl). The reaction can be applied to a very broad range of alkenes to generate haloamines and haloethers with high isolated yields. With DBU as the base, metal-free C–H amination of aryl olefins has also been achieved with good yields.

An efficient amination reaction of 3-substituted benzofuran-2(3H)-ones promoted by cesium carbonate was developed. A putative mechanism involving a single-electron-transfer event was proposed, which represents a new reactivity for benzofuran-2(3H)-ones.

Quantitative knowledge of the fluorinating strength of electrophilic N–F reagents is of crucial importance for rational design and optimization of novel reagents and new reactions. Herein, we report the first systematic computation of fluorinating potentials of 130 electrophilic N–F reagents in two commonly used solvents dichloromethane and acetonitrile in terms of the N–F bond heterolysis energies as expressed by the fluorine plus detachment (FPD) values. The calculated FPD scales of 130 N–F reagents cover a range from 112.3 to 290.4 kcal mol–1 and 110.9 to 278.4 kcal mol–1 in dichloromethane and acetonitrile, respectively. This comprehensive FPD database provides a valuable quantitative guide for studying the influence of structural variation on the fluorinating strength of the N–F reagents, opening a door to the rational design of novel reagents with appropriate fluorinating strength for specific purposes. It is demonstrated that the FPD values can reproduce the reactivity order for electrophilic N–F r...

Review: factors limiting the stability and recent developments in strategies to increase the stability of organic solar cells; 381 refs.

An asymmetric 1,6-conjugate addition of thioacetic acid with para-quinone methides has been developed by using chiral phosphoric acid catalysis in the presence of water. A series of sulfur-containing compounds were thus obtained in high yields with good to excellent enantioselectivities. Theoretical studies indicated that the water-bridged proton transfer is a potentially favorable reaction pathway. An unprecedented O-H⋅⋅⋅π interaction between water and the aromatic nucleus of chiral phosphoric acid was discovered to contribute significantly to the stereocontrol in the catalysis.

An asymmetric Michael reaction of 2-alkyl substituted benzofuran-3(2H)-ones with nitroolefins via bifunctional tertiary-amine squaramide catalysis is developed.

A visible-light-mediated, organic photocatalytic stereoselective radical cascade cyclization of polyprenoids is described. The desired cascade cyclization products are achieved in good yields and high stereoselectivities with eosin Y as photocatalyst in hexafluoro-2-propanol. The catalyst system is also suitable for 1,3-dicarbonyl compounds, which require only catalytic amounts of LiBr to promote the formation of the corresponding enols.

An efficient asymmetric allylic alkylation reaction with respect to 3-alkylidene oxindoles and racemic Morita–Baylis–Hillman carbonate has been achieved by using a chiral biscinchona alkaloid catalyst, which delivers the γ-substituted alkylideneoxindoles with a chiral tertiary center in moderate to good yields (up to 92%) and very good enantioselectivities (up to >99% ee).

A highly enaantioselective synthesis of the title heterocycles becomes possible in the presence of β-ICD (Ia) with MeOH as the additive [cf.

Chiral 3,3′-disubstituted benzofuranones are synthesized from the title addition in excellent yields with very good diastereoselectivities and enantioselectivities.

A highly enantioselective [4+2] annulation with respect to allenoates and 3-olefinic oxindoles catalyzed by Lewis base was reported, which proved to be an efficient way to synthesize chiral dihydropyran-fused indoles. The cycloaddition products were generally obtained in high yields (up to 98%) with very good enantioselectivities (up to 94% enantiomeric excess).

The aerobic oxidative dehydrogenation of α-branched primary amines and cyclic secondary amines to imines without any metal cocatalyst is presented

Starting from 2-benzylidenebenzofuran-3-ones the synthesis of chiral dihydropyran-fused benzofurans is elaborated.

Both compounds exhibit significant inhibition against PC12 cell damage induced by rotenone.

This simple transfer diazenylation reaction exhibits good functional group compatibility, and provides a convenient approach for the synthesis of highly functionalized azo compounds.

Bismuth triflate shows higher activities in the intramolecular addition of sulfonimine (XI) to give vinyl amine (XII).

The first effective example of asymmetric conjugate addition–protonation reactions of thiols to α-substituted vinyl ketones by chiral primary amine catalysis is reported. A simple chiral primary–tertiary diamine catalyst derived from l-phenylalanine was found to promote the sulfa-Michael addition–protonation reactions with good to excellent enantioselectivity.

N,N-Dimethylethylenediamine·TfOH is found to be an efficient catalyst for the direct α-allylic alkylation of unmodified aldehydes with allylic alcohols.

The first example of the enantioselective conjugate addition of alkenes to enones, catalyzed by chiral primary amines are reported.The reaction is enabled by chiral primary amines through a typical iminium ion cycle.

The title compound shows good antioxidant activity and is able to scavenge the diphenyl picrylhydrazyl radical with an EC50 of 20.6 μg/ml.

A highly enantioselective Diels–Alder reaction of 3-olefinic benzofuran-2-ones with polyenals catalyzed by diphenylprolinolsilyl ether through a trienamine activation strategy was developed.

The reactions of α-substituted vinyl aldehydes are a summary of previous results and are not shown.

The exchange of the metal ion from In(III) to Sc(III) in a binary acid catalyst leads to a switch in the diastereoselectivity of [4 + 2] cycloadditions.

This reaction sequence yields the spiro-products with adjacent quaternary and tertiary stereocenters with excellent enantioselectivities.

The regioselectivity of the formation of spiro-bis-lactones from benzofuran-2,3-diones and α,β-unsaturated β-aryl-substituted aldehydes is investigated with different N-heterocyclic carbene catalysts.

The reaction proceeds with moderate to high dia- and high enantioselectivities for the symmetrical and unsymmetrical diaryldienones.

The title reaction affords the desired spirocyclic products (III)/(IV) and (VI)/(VII) in good to high yields and with moderate to good regioselectivities.

Nazarov reaction of aryl vinyl β-ketoesters is optimally catalyzed by a binary acid catalyst consisting of In(OTf)3 and diphenyl phosphoric acid (DPP).

Qunidine-catalyzed treatment of Boc-protected 3-substituted oxindoles with (arylthio)phthalimides is found to allow a highly enantioselective access to 3-sulfurated derivatives of type (III) and (V) which are of biological and chemical interest.

Selective H transfer by ABC: A new asymmetric binary acid catalyst was developed to promote 1,5-H transfer specifically and stereoselectively in tert-aminocyclization reactions with excellent activity, high enantioselectivity, and broad substrate scope. The H atom (in red) was proven to transfer through a stereospecific suprafacial pathway (see scheme).

A bifunctional Cinchona alkaloid-based organocatalyst efficiently catalyzes the asymmetric Michael addition of 3-substituted benzofuranones (I) and (IV) with bis(phenylsulfonyl)ethylene (II).

The amine efficiently promotes the enantioselective formation of the title ketones and related compounds.

Michael reaction of a variety of 3-substituted benzofuranones with β-nitroolefins proceeds efficiently in the presence of a tertiary amine—thiourea organocatalyst to give benzofuranones bearing an all-carbon quaternary stereocenter at position 3.

Asymmetric Friedel—Crafts reaction of α-substituted acroleins with various indoles gives the desired products in high yields and enantioselectivities.

Novel types of non-covalently immobilized polyoxometalate (POM) catalysts using magnetic nanoparticles as support are prepared.

A series of novel phthiobuzone analogues (III) is synthesized and tested in vitro for their anti-herpes simplex virus (HSV) activity.

The alkaloid efficiently promotes the coupling of 3-substituted benzofuranones with carbonates giving 3,3-disubstituted benzofuranones with moderate to high diastereo- and enantioselectivity.

Swapping the anions of an indium Lewis acid leads to a remarkable regioselectivity switch between asymmetric 1,2- and 1,4-addition reactions of N-protected indoles (II) and β,γ-unsaturated α-keto esters (III).

Aqueous acetaldehyde solution and paraldehyde can be conveniently applied in this reaction.

The immobilization of organocatalysts is one of the most explored approaches to overcome the limitations associated with organocatalytic systems such as high catalyst loading, difficult product separation and catalyst recycling. When compared with the commonly used covalent immobilization methods, which usually involve tedious synthetic manipulations, the non-covalent attachment of organocatalysts to supports offers facile and modular construction of immobilized chiral catalysts with maintained or even improved activity and stereoselectivity. This review summarizes the successful application of non-covalent interactions, such as acid–base interaction, ion–pair interaction, hydrophobic interaction and so on, in assembling recoverable and reusable organocatalysts.

The diamine efficiently promotes the kinetic resolution of racemic syn-aldols of cyclohexanones in [bmim]BF4.

Asymmetric Michael addition of 3-substituted oxindoles (I) and (IV) towards acrylonitrile (II) proceeds efficiently in the presence of a thiourea organocatalyst to give oxindoles containing an all-carbon quaternary stereocenter at position 3 and an additional nonadjacent stereocenter in the side chain.

1,1-Disubstituted terminal alkenes remain challenging substrates in asymmetric epoxidation reactions. In this study, chiral primary amines are shown to catalyze the asymmetric epoxidation of α-substituted acroleins, a versatile type of 1,1-disubstituted terminal alkene. Among various chiral primary amines explored, the chiral primary-tertiary vicinal diamine derived from trans-1,2-diphenylethane-1,2-diamine is identified as the optimal catalyst, which, in combination with 5-sulfosalicyclic acid (5-SSA), exhibits good catalytic activity (up to 95 % yield) and enantioselectivity (up to 88 % ee). Aqueous 2 M sodium chloride was found to be the optimal reaction media.