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Phosphoranes 2 are identified as a class of effective Lewis bases to activate chiral (salen)AlCl complex 1 to enhance its electrophilicity. Accordingly, a three-component catalyst system consisting of complex 1, phosphorane 2e, and Ph3PO is developed as a powerful tool for asymmetric ketone cyanosilylation. In particular, an unprecedented highly enantioselective cyanosilylation of linear aliphatic ketones is achieved. A tandem Wittig-cyanosilylation sequence starting from phosphorane 2a and enals 10 is further achieved, which internally utilizes the Ph3PO byproduct and remaining phosphorane 2a as cocatalysts for cyanosilylation of α,β,γ,δ-unsaturated enones, providing atom-efficient access to valuable chiral conjugated dienes and enynes. The high efficiency of the cyanosilylation originates from orthogonal activation of both (salen)AlCl complex 1 and cyanotrimethylsilane by the phosphorane and Ph3PO, respectively. This mechanistic insight is supported by NMR, MS, and ReactIR analyses and DFT calculations. Furthermore, the formation of charged complexes through the activation of chiral complex 1 by phosphorane 2a is confirmed by electrical conductivity experiments. [ABSTRACT FROM AUTHOR]

The nickel-catalyzed reductive coupling of alkynes and imines with Et2Zn as a reductant by using electron-rich phosphine ligands has been developed, affording various allylic amines with high yields and excellent chemoselectivities. Chiral induction was also achieved in this reductive coupling reaction when a nickel catalyst containing a chiral spiro phosphine ligand was used. [ABSTRACT FROM AUTHOR]

A novel strategy for the asymmetric construction of functionalized 4-aryl-3,4-dihydrocoumarins and 4-aryl-3,4-dihydroquinolin-2-ones via an intramolecular vinylogous Rauhut-Currier reaction of para-quinone methides (p-QMs) under the bifunctional catalysis of chiral amine-phosphine is described. This intramolecular mode for the catalytic enantioselective 1,6-conjugate addition of p-QMs has been explored for the first time, delivering two types of synthetically important heterocycles in high yields and enantioselectivites. [ABSTRACT FROM AUTHOR]

The article explores the construction of a multifunctional 3D ferroelectric and nonlinear optical (NLO)-active porous metal-organic frameworks (MOFs). It says that MOFs can be applied in host-guest molecular interactions, catalysis, gas storage, and separation. It provides a framework with chiral tetrahedral secondary building units (SBUs) made by various connections of carboxylate groups to zinc units to form a noncentrosymmetric complex with occupying ferroelectric and NLO properties.

The article discusses the development of highly enantioselective hydrogenation of simple N-unprotected enamines catalyzed by a Rh(I) complex of chiral spiro phosphonite ligand (S)-1c, which provided a straightforward method for the synthesis of chiral tertiary amines with great ee values. Chiral amines are an important class of compounds in organic and pharmaceutical synthesis. The catalytic asymmetric hydrogenation of N,N-diakylenamines is one of the most straightforward accesses to the optically active tertiary 1,2-diarylethanamines.

The direct asymmetric vinylogous Mannich reaction of 3,4-dihalofuran-2(5H)-one with aldimine catalyzed by quinine was first reported, and γ-butenolides have been obtained in excellent yield (up to 98%) and enantioselectivities (up to 95% ee). The synthetic applications of this protocol are demonstrated in the preparations of γ-substituted amino butyrolactones and vicinal amino alcohols. [ABSTRACT FROM AUTHOR]

A highly diastereoselective and enantioselective Michael addition of α-substituted isocyanoacetates with maleimides catalyzed by bifunctional tertiary amine thioureas has been developed. Various chiral succinimide derivatives bearing adjacent quaternary and tertiary stereocenters were prepared in excellent yields (up to 98%), diastereoselectivities (up to 99:1), and enantioselectivities (up to 98% ee). The synthetic utility of chiral succinimide derivatives is also demonstrated in the preparation of h5-HT1d receptor agonist motifs. [ABSTRACT FROM AUTHOR]

A series of simple chiral primary amino acids were first successfully applied to promote the enantioselective α-amination of branched aldehydes with azadicarboxylates and the desired adducts bearing quaternary stereogenic centers were obtained in excellent yields (up to 99%) and enantioselectivities (up to 97% ee). [ABSTRACT FROM AUTHOR]

The article discusses the highly enantio selective insertion of carbenoids into oxygen-hydrogen bonds phenols, which is considered an effective approach to chiral α-aryloxycarboxylic esters. It is inferred that the enatioselectivity waned when the Cu/biazaferrocene catalyst was applied to phenol substrates. Moreover, the optically active α-arloxypropionates and the related acids were synthesized conveniently using the copper complexes of chiral spiro bisoxazolines as crystalysts.