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Comprehensive Summary: Herein, we reported a precise de novo synthesis of chiral 3,4‐dihydroquinazoline frameworks via a one‐pot anionic stereogenic‐at‐cobalt(III) complex‐catalyzed enantioselective Ugi‐azide/Pd‐catalyzed cyclization sequence. This powerful protocol involves 5 components and 2 catalytic systems, delivering chiral 3,4‐dihydroquinazolines with excellent enantioselectivities (up to 94% ee). The preliminary antifungal experiments suggest that both Ugi‐adducts and 3,4‐dihydroquinazolines have great potential in inhibiting plant pathogens such as Trichoderma viride and Fusarium graminearum. [ABSTRACT FROM AUTHOR]

A privileged strategy has been developed for the precise construction of enantioenriched azaspiro polycyclic scaffolds. Structurally diverse azaspiro polycycles bearing multiple contiguous stereocenters are obtained with excellent results (up to 99:1 e.r., >95:5 d.r.) via sequential enantioselective four-component Ugi reactions/post-Ugi transformations with substrates containing prerequisite functional groups in the presence of anionic stereogenic-at-cobalt(III) complexes. [ABSTRACT FROM AUTHOR]

A new synthetic approach to novel axially chiral iodobenzocarbazole derivatives based on the highly enantioselective intramolecular iodoarylation of linked alkyne‐indole systems was developed by using the versatile chiral catalyst, stereogenic‐at‐cobalt(III)‐complex, through an axially chiral iodinated vinylidene o‐quinone methide (IVQM) intermediate. This protocol provides 21 examples in excellent yields with good to high enantioselectivities (up to 96 % yield, 98 % ee). Furthermore, the introduced iodine atoms can easily be converted into other functional groups. [ABSTRACT FROM AUTHOR]

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A desymmetrizing silylation of aromatic diols is reported. The previously unknown asymmetric silyl ether formation of phenol derivatives is achieved by applying List's counteranion directed silylation technique. A silylium‐ion‐like silicon electrophile generated from an allylic silane paired with an imidodiphosphorimidate (IDPi) enables enantioselective discrimination of achiral 1,1′‐biaryl‐2,6‐diols. The enantioselectivity of that desymmetrization is further improved by a downstream kinetic resolution, converting the monosilylated minor enantiomer into the corresponding, again achiral bissilylated diol. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: A highly efficient kinetic resolution of racemic thioanilide atropisomers via C(sp3)−H arylation has been achieved by a hybrid palladium catalyst bearing an anionic chiral CoIII‐complex and a phosphoramidite ligand, leading to both enantioenriched atropisomeric arylation thioanilides (up to 99% ee) and N‐Me atropisomeric thioanilides (up to 99% ee), simultaneously. The remained enantioenriched substrates can be arylated again by using an achiral anionic ligand to give the enantiomer with the opposite configuration. [ABSTRACT FROM AUTHOR]

We describe a catalytic asymmetric iminium ion cyclization reaction of simple 2-alkenylbenzaldimines using a BINOL-derived chiral N-triflyl phosphoramide. The corresponding 1-aminoindenes and tetracyclic 1-aminoindanes are formed in good yields and high enantioselectivities. Further, the chemical utility of the obtained enantiopure 1-aminoindene is demonstrated for the asymmetric synthesis of (S)-rasagiline. [ABSTRACT FROM AUTHOR]

A hybrid palladium catalyst assembled from a chiral phosphoric acid (CPA) and thioamide enables a highly efficient and enantioselective β‐C(sp3)−H functionalization of thioamides (up to 99 % yield, 97 % ee). A kinetic resolution of unsymmetrical thioamides by intermolecular C(sp3)−H arylation can be achieved with high s‐factors. Mechanistic investigations have revealed that stereocontrol is achieved by embedding the substrate in a robust chiral cavity defined by the bulky CPA and a neutral thioamide ligand. [ABSTRACT FROM AUTHOR]

An unusual hybrid palladium catalyst containing an anionic chiral CoIII complex and a chiral phosphoramidite ligand shows a high capacity for catalyzing asymmetric thioamide‐directed C(sp3)−H arylation and delivers excellent yield and enantioselectivity (up to 99 % yield, 99 % ee). Significant synergy between the chiral ligand and the anion in terms of stereochemical control was observed. Mechanistic investigations have revealed both the nature of the C−H activation and the origin of the enantioselectivity. An unusual hybrid palladium catalyst containing an anionic chiral CoIII complex and a chiral phosphoramidite ligand shows a high capacity for catalyzing asymmetric thioamide‐directed C(sp3)−H arylation and delivers excellent yields and enantioselectivity (up to 99 % yield, 99 % ee). Significant synergy between the chiral ligand and the anion in terms of stereochemical control was observed. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Brønsted acids of anionic chiral CoIII complexes act as bifunctional phase-transfer catalysts to shuttle the substrates across the solvent interface and control stereoselectivity. The diastereomeric chiral CoIII-templated Brønsted acids, with the same chiral ligands, enabled a switch in the enantioselective bromoaminocyclization of olefins to afford the two enantiomers of 2-substituted pyrrolidines with high enantioselectivities (up to 99:1 e.r.). [ABSTRACT FROM AUTHOR]

Brønsted acids of anionic chiral CoIII complexes act as bifunctional phase-transfer catalysts to shuttle the substrates across the solvent interface and control stereoselectivity. The diastereomeric chiral CoIII-templated Brønsted acids, with the same chiral ligands, enabled a switch in the enantioselective bromoaminocyclization of olefins to afford the two enantiomers of 2-substituted pyrrolidines with high enantioselectivities (up to 99:1 e.r.). [ABSTRACT FROM AUTHOR]

The sodium salts of anionic chiral cobalt(III) complexes (CCC−Na+) have been found to be efficient catalysts of the asymmetric Povarov reaction of easily accessible dienophiles, such as 2,3-dihydrofuran, ethyl vinyl ether, and an N-protected 2,3-dihydropyrrole, with 2-azadienes. Ring-fused tetrahydroquinolines with up to three contiguous stereogenic centers were thus obtained in high yields, excellent diastereoselectivities ( endo/ exo up to >20:1), and high enantioselectivities (up to 95:5 e.r.). [ABSTRACT FROM AUTHOR]

The sodium salts of anionic chiral cobalt(III) complexes (CCC−Na+) have been found to be efficient catalysts of the asymmetric Povarov reaction of easily accessible dienophiles, such as 2,3-dihydrofuran, ethyl vinyl ether, and an N-protected 2,3-dihydropyrrole, with 2-azadienes. Ring-fused tetrahydroquinolines with up to three contiguous stereogenic centers were thus obtained in high yields, excellent diastereoselectivities ( endo/ exo up to >20:1), and high enantioselectivities (up to 95:5 e.r.). [ABSTRACT FROM AUTHOR]

We discuss the dissipative nonlinear Schrödinger equation (NLSE) with a variable coefficient in blood vessels via a NLSE-based constructive method and obtain exact nonautonomous soliton solutions including bright soliton solutions on continuous wave (cw) and cnoidal wave (cnw) backgrounds. Moreover, the dynamical behaviors of these soliton solutions are studied. The impact of the cw background on the separating and interactive soliton behaviors is investigated. These behaviors of the soliton can be modulated by adjusting the amplitude of background wave. The propagation behaviors of solitons on the cnw background in different dispersion systems are also studied. These results are potentially useful for future experiments in various blood vessels. [ABSTRACT FROM AUTHOR]

A hybrid chiral palladium catalyst for the asymmetric arylation of saturated aza‐heterocycles is described by X. Zhang, L.‐Z. Gong, and co‐workers in their Communication on page 1803 ff. The demonstrated hybrid catalyst consists of a chiral phosphoramidite ligand and a chiral CoIII‐based counteranion. It exhibits a high capacity for catalyzing asymmetric thioamide‐directed C(sp3)–H arylation and offers excellent yield and enantioselectivity (up to 99% yield, 99% ee). [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)