Electronic properties of the ligands switch diastereoselectivity in Cu-catalyzed 1,3-dipolar cycloaddition azomethine ylides to nitroalkenes: exo- or endo-pyrrolidines were obtained with high diastereo- and enantioselectivities presence different chiral (phosphanylferrocenyl)oxazoline (e.g. 3 a, b).

Chiral catalysts tolerating photochemical reactions are in great demand for the vast development of visible-light-induced asymmetric synthesis. Now, chiral octahedral complexes based on earth-abundant metal and N4 ligands reported. One well-defined CoII -complex is shown to be an efficient catalyst conjugated addition enones by alkyl acyl radicals, providing synthetically valued ketones 1,4-dicarbonyls 47->99 % yields with up 97:3 e.r.

Abstract The combination of a new bifunctional phosphine and an acrylate generate zwitterion in situ it serves as efficient catalyst for asymmetric reactions through homogeneous ion‐pairing mode. This catalytic system has been successfully applied to Mannich‐type give excellent results demonstrates broad substrate scope. Such reactivity is not accessible with general organophosphine modes. Preliminary investigations into the mechanism are also presented.

A novel P(NMe2)3-mediated reductive [1+4] annulation reaction between isatins and enones has been developed, providing the facile synthesis of spirooxindole-dihydrofurans. This unveils first practical approach to construct five-membered cyclic motifs via a Kukhtin-Ramirez adduct involved mode.

The first interrupted asymmetric hydroaminomethylation reaction was developed. challenging trans-1,2-disubstituted olefins were employed as substrates, and a series of valuable chiral pyrrolidinones pyrrolidines obtained in high yields with regioselectivities excellent enantioselectivities. Several synthetic transformations conducted, demonstrating the utility our method. A creative route for synthesis vernakalant Enablex also

Herein, a practical, convenient and facile construction of highly functionalized 2-pyrrolidinone enabled by N-Heterocyclic Carbene (NHC)-catalyzed radical tandem cyclization has been developed.

Die elektronischen Eigenschaften der Liganden bestimmen die Diastereoselektivität Cu-katalysierten 1,3-dipolaren Cycloadditionen von Azomethin-Yliden an Nitroalkene: exo- oder endo-Pyrrolidine 4 wurden mit hohen Diastereo- und Enantioselektivitäten erhalten, je nachdem, welcher chirale (Phosphanylferrocenyl)oxazolin-Ligand eingesetzt wurde (siehe 3 a b im Schema). Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2001/2006/z503672_s.pdf...

Abstract An unusual formal [1+4] annulation of α‐dicarbonyl compounds with 1,1‐dicyano‐1,3‐dienes has been realized, leading to facile syntheses cyclopentenimines and cyclopentenones in a unique manner. Mechanistic investigation implies that this reaction takes place through P(NMe 2 ) 3 ‐mediated cyclopropanation followed by base‐catalyzed cyclopropane rearrangement. It therefore represents an unprecedented mode involving Kukhtin–Ramirez adducts.

Abstract A novel method for the regioselective C2‐chlorination of heterocyclic N ‐oxides has been developed. PPh 3 /Cl CCN were used as chlorinating reagents and desired N‐heterocyclic chlorides obtained smoothly in satisfactory yields. The reactions proceeded a highly efficient selective manner across broad range substrates demonstrating excellent functional group tolerance. In addition, this chlorination reaction can be modification scaffolds appealing ligands pharmaceuticals.

Herein, an NHC (N-heterocyclic carbene)-catalyzed radical coupling reaction between aldehydes and azobis(isobutyronitrile) (AIBN) has been developed. This method provides efficient convenient approach for the synthesis of β-ketonitriles containing a quaternary carbon center (31 examples, up to >99% yield) utilizing commercially available substrates. protocol features broad substrate scope, good functional group tolerance, high efficiency under metal-free mild conditions.

Herein, an N-heterocyclic carbene (NHC) catalyzed formal [3 + 3] annulation of δ-acetoxy allenoates with 1C,3O-bisnucleophiles for the construction 4H-(fused)pyrans has been developed. This protocol provides a facile method to synthesize highly functionalized 4H-pyrans and broad substrate scope (30 examples, up 77% yield).

Abstract The combination of a new bifunctional phosphine and an acrylate generate zwitterion in situ it serves as efficient catalyst for asymmetric reactions through homogeneous ion‐pairing mode. This catalytic system has been successfully applied to Mannich‐type give excellent results demonstrates broad substrate scope. Such reactivity is not accessible with general organophosphine modes. Preliminary investigations into the mechanism are also presented.

A photopromoted NHC catalyzed asymmetric [4+2] annulation of saccharine-derived azadienes and α -diazoketones was developed, affording the corresponding sultam-fused dihydropyridinones efficiently (up to 80% yield, 99% ee >20 : 1 d.r.).

The Wittig reaction is a reliable method for synthesizing alkenes from phosphorous ylides (P-ylides) and carbonyls, thus widely applied in medicine pharmaceutical production.

Photoinduced enantioselective strategies provide an efficient way to access chiral all-carbon quaternary stereocenters. Compared with the well-developed metal-catalyzed asymmetric conjugate addition of organometallic reagents enones, construction stereocenters through a radical process still remains challenging, especially for acyclic enones due their enhanced conformational mobility. Herein, we disclose photoinduced cobalt-catalyzed coupling α,β-unsaturated 2-acyl imidazoles and...

An NHC-catalyzed [2 + 4] cyclization of alkynyl ester with α,β-unsaturated ketone to form a pyran scaffold was developed successfully. The cheap and easily available starting materials, mild reaction conditions, moderate excellent yields, high atom economy make this strategy attractive for the syntheses highly substituted 4H-pyran derivatives.

Abstract A visible‐light‐induced highly practical catalyst‐free Wolff rearrangement/domino [4+2] cycloaddition of 2‐benzothiazolimines with α‐diazo ketones has been developed. This protocol provides a concise and facile synthetic approach to construct broad range benzothiazolopyrimidine derivatives bearing quaternary carbon center under mild reaction conditions high isolated yields excellent diastereoselectivities (up >99% yield >20 : 1 d.r.).

Herein, an N-heterocyclic carbene (NHC) catalyzed radical tandem cyclization reaction of

Abstract Diverse transformations of allenoates catalyzed by Lewis bases have emerged as a powerful platform for generating new chemical entities in organic synthesis. Herein, an N ‐heterocyclic carbene (NHC) [3+3] cyclization 2‐(acetoxymethyl)buta‐2,3‐dienoates with 1 C,3O‐bisnucleophiles has been developed. This approach provides facile method to synthesize highly functionalized 4 H ‐pyran derivatives broad substrate scope (31 examples, up 83 % yield).

An NHC-catalyzed regiospecific allylation of α-substituted allenoates with MBH carbonates derived from aryl aldehyde furnished highly functionalized 1,5-enynes.

Herein, an efficient (

A facile NHC-catalyzed [2 + 4] annulation of allenoates with 2,3-dioxypyrrolidine derivatives was discovered, which paved a new avenue for the construction highly substituted pyranopyrrole moderate to good yields, high atom economy and mild reaction conditions.