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An efficient temperature‐dependent organocatalyzed asymmetric formal [3+2] cycloaddition reaction of α‐substituted isocyanoacetates to β‐trifluoromethylated enones by cinchona alkaloid‐derived squaramide has been investigated, affording the optically active trifluoromethylated 2‐pyrrolines in excellent yields (up to 98 %) and high stereoselectivities (>20:1 dr, up to >99 % ee) under mild conditions. [ABSTRACT FROM AUTHOR]

Abstract: Cinchona alkaloid derived catalyst cat. 5 prepared from β-isocupreidine (β-ICD) was found to be a fairly effective organocatalyst for the nucleophilic promoted asymmetric [4+2] cycloaddition reaction of salicyl N-tosylimines and allenic esters to give the corresponding adducts in up to 80% yield, 87% ee. [Copyright &y& Elsevier]

Abstract: Axially chiral phosphine–oxazoline ligand L6 was found to be a fairly effective chiral ligand in silver(I)-catalyzed asymmetric Mannich reaction of N-Boc aldimines with trimethylsiloxyfuran to give the corresponding adducts in up to 97% yield, 7:1 dr and 86% ee (major diastereoisomer). [Copyright &y& Elsevier]

Abstract: Axially chiral C 2-symmetric N-heterocyclic carbene (NHC) palladium diaquo complexes 1a and 1b, derived from (R)-BINAM, are effective catalysts for the enantioselective α-hydroxylation of β-keto esters using oxaziridine 2a as the oxidant to give the corresponding products in high yields along with moderate enantioselectivities. [ABSTRACT FROM AUTHOR]

In the past decade, the asymmetric Morita-Baylis-Hillman (MBH)/aza-Morita-Baylis-Hillman (aza-MBH) reaction has attracted great attention because it leads to the formation of densely functionalized products in a catalytic and atom-economic way. The MBH/aza-MBH adducts can be further applied in a wide variety of organic synthesis, such as peptide synthesis and heterocyclic compounds synthesis. After a lot of attempts to improve the enantioselectivity, many types of chiral organocatalysts have been identified as highly enantioselective organocatalysts in MBH/aza-MBH reaction. Especially, certain "privileged chiral catalysts" are highly enantioselective in MBH/aza-MBH reaction, which are designed and developed through introducing bi-/multi-functional groups on the so-called "privileged structures" such as cinchona alkaloids, BINAP/BINOL. This review summarizes the exciting advances about the design and development of chiral catalysts derived from "privileged structures" and their applications in asymmetric MBH/aza-MBH reaction. [ABSTRACT FROM AUTHOR]

Abstract: The catalytic asymmetric addition of arylboronic acids to N-Boc imines generated in situ from stable and easily prepared α-carbamoyl sulfones was realized by using chiral cationic C 2-symmetric N-heterocyclic carbene (NHC) Pd2+ diaquo complexes 1a–c as the catalysts, producing the corresponding adducts in good to high yields (up to 89%) and good to high enantioselectivities (up to 90% ee). [Copyright &y& Elsevier]

Abstract: A series of novel bifunctional chiral phosphine-containing Lewis bases were synthesized and successfully applied to the asymmetric Morita–Baylis–Hillman reaction of aldehydes with methyl vinyl ketone (MVK) and ethyl vinyl ketone (EVK) to give the corresponding adducts in moderate yields and enantioselectivities under mild reaction conditions. [Copyright &y& Elsevier]

Review: [41 refs. [ABSTRACT FROM AUTHOR]

Palladium-catalyzed asymmetric formal [3+2] cycloadditionof vinyl cyclopropanes and β,γ-unsaturated α-ketoesters proceeded smoothly in the presence of chiral imidazoline–phosphineligands to give the corresponding highly functionalized cyclopentanesin good yields along with high diastereo- and enantioselectivitiesunder mild conditions. [ABSTRACT FROM AUTHOR]

Abstract: A class of axially chiral NHC–Au(I) complexes has been applied to the asymmetric Friedel–Crafts/cyclization reaction of nitrogen-tethered 1,6-enynes 14 with indole derivatives 15, affording the corresponding Friedel–Crafts and intramolecular cyclization products 16 in good yields and with moderate ee values under mild conditions. [Copyright &y& Elsevier]

Abstract: Chiral bidentate phosphine-imine type ligand L9 is fairly effective in the asymmetric allylic substitution of 1,3-diphenylpropenyl acetate with dimethyl malonate to give the corresponding adduct in moderate yield and good ee. [Copyright &y& Elsevier]

Abstract: Axially chiral BINIM–Ni(II) complexes are effective catalysts in the asymmetric chlorination of 3-substituted oxindoles and give the corresponding chlorinated adducts in good yields and up to 88% ee. [Copyright &y& Elsevier]

Abstract: Chiral phosphine-Schiff base type ligand L3 prepared from (R)-(−)-2-(diphenylphosphino)-1,1′-binaphthyl-2′-amine was found to be a fairly effective chiral ligand for the Pd(II)-catalyzed and diethylzinc-mediated enantioselective umpolung allylation of aldehydes to give homoallylic alcohols in good yields, moderate enantioselectivities and high syn diastereoselectivities. [ABSTRACT FROM AUTHOR]

Abstract: Chiral C 2-symmetric N-heterocyclic carbene (NHC) palladium diaquo complexes 5a–c and the chiral C 2-symmetric NHC-palladium complexes 5d and 5e prepared from (R)-BINAM or H8-(R)-BINAM could be used as the catalysts for the enantioselective arylation of arylaldehydes with arylboronic acids in which NHC-Pd complex 5a was found to be fairly effective in this reaction to give the corresponding adducts in moderate enantioselectivities along with moderate to good yields. [ABSTRACT FROM AUTHOR]

Abstract: Chiral phosphine-Schiff base-type ligand L1 prepared from (R)-(−)-2-(diphenylphosphino)-1,1′-binaphthyl-2′-amine was found to be a fairly effective ligand for Cu(I)-promoted enantioselective α-hydroxylation of β-keto esters using oxaziridine 2a as the oxidant to give the corresponding products in high yields along with moderate enantioselectivities. [Copyright &y& Elsevier]

The reactions are catalyzed by a novel Cinchona alkaloid-derived organocatalyst and different spirocyclic products are obtained depending on the reaction conditions and the ratios of reagents. [ABSTRACT FROM AUTHOR]