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This Review summarizes the advances in the construction of all-carbon quaternary stereocenters via catalytic enantioselective desymmetrization of prochiral and meso-compounds, highlights the power and potential of this strategy in the total synthesis of natural products and biologically active compounds, and outlines the synthetic opportunities still available.

The high efficiency of this reaction relies on orthogonal activation of the AlCl(salen) complex and Tms—CN by the phosphorane and POPh3, respectively.

We report an unprecedented sequential Au(i)/bifunctional tertiary amine catalysis, which enables a tandem C-H functionalization of weak nucleophiles (anisoles or thiophenes) and asymmetric Michael addition for the highly enantioselective synthesis of quaternary oxindoles from diazooxindoles and nitroenynes.

A highly enantioselective palladium-catalyzed hydrogenation of a series of linear and cyclic α-iminophosphonates has been achieved, providing efficient access to optically active α-aminophosphonates with up to 99% ee.

With the aid of an axially chiral 2,2′-bipyridine ligand, we have successfully developed a palladium-catalyzed method for the enantioselective arylation of N-tosylarylimines, furnishing the chiral diarylmethamines with high yields and enantioselectivities under very mild conditions. An exogenous base was avoided and imine hydrolysis was inhibited in this transformation.

A streamlined method for the enantioselective synthesis of 2-amino-4H-chromenes from readily available 2-alkyl-substituted phenols and active methylene compounds bearing a cyano group with up to 97% ee is presented. This reaction is a cascade procedure including manganese dioxide mediated C-H oxidation for the generation of o-quinone methides and bifunctional squaramide-catalyzed Michael addition/cyclization.

Michael addition/cyclization reaction of o-quinone methides generated in situ from substrates (I) and (VI) with active methylene compounds gives chromene derivatives in excellent yields with high enantioselectivities.

This perspective describes recent progress in asymmetric catalysis with chiral only-at-metal complexes displaying Λ/Δ enantiomorphs in the absence of central chirality within the ligands, with an emphasis on Ir(III) and Rh(III) systems. The good selectivity achieved when using these complexes in asymmetric catalysis has been demonstrated in asymmetric transformations through various mechanisms, including hydrogen-bond donor–acceptor, secondary amine or Bronsted base hydrogen-bond donor bifunctional catalysis, Lewis acid and photoredox catalysis under mild reaction conditions. This perspective highlights the widening field of chiral-at-metal catalysis and presents a selection of asymmetric transformations which have been successfully carried out using them.

Spirocyclopropyl oxindoles are widely present in natural products and bioactive molecules. In addition, they play a significant role as a type of donor–acceptor (DA) cyclopropanes in catalytic reactions. Four distinct pathways have been developed for the asymmetric synthesis of this framework, which nicely show the potential of organocatalytic and metal catalyzed asymmetric cyclopropanation in the creation of spirocyclic compounds. This minireview summarizes these complementary methods to synthesise optically active spirocyclopropyl oxindoles bearing various functional groups, discusses the difference and advantages of each method, and summarizes synthetic opportunities that still exist.

The new title compound is prepared from a mixture of In2S3 and CaS in the molar ratio of 3:2 using NaBr as a reactive flux (950 °C, 120 h

We report an organocatalytic addition of nitromethane to aryl α-ketoester-derived N-tosyl ketimines or isatin-derived N-tert-butyloxycarbonyl ketimines, catalyzed by 1,8-diazabicyclo[5.4.0]undec-7-ene (1–5 mol %). Initial screenings reveal that the reaction with a quinine-derived bifunctional catalyst, which features a C6 phenolic hydroxy group, achieved up to 71 % ee.

The catalytic asymmetric synthesis of 3,3-disubstituted oxindoles, a big family of privileged scaffolds in natural products and drugs, is of current interest. Recently, the catalytic asymmetric functionalization of diazooxindoles emerges as a potentially general and flexible strategy for this purpose, with several notable examples coming out in 2013. In this digest, synthetic applications of diazooxindoles have been summarized and discussed, which might be helpful for readers to understand the special properties of this type of donor/acceptor cyclic diazo reagent and to develop new catalytic asymmetric reactions.

The reaction applies a wide range of alkenes, including cyclic, cis- and trans-1,2-disubstituted as well as 1,1-disubstituted ones.

The reaction represents the first example of the aminomethylation of both α-alkyl and α-aryl-substituted nitroacetates under catalyst-free conditions.

Cu2MgSiS4 (I), Cu2MgGeS4 (II), and Cu2MgSiSe4 (III) are synthesized by solid state reactions of stoichiometric mixtures of the elements (quartz tube, 950 °C, 5 d).

A systematic study is presented for the reaction of 3-hydroxyindoles with thiols and alcohols in the presence of perchloric acid.

The use of easily available starting materials as well as a broad substrate scope make the process useful.

A wide range of substituted isatins is allylated under aerobic conditions using Hg(ClO4)2·3H2O.

The new compounds Sr2Y2.67Sn3S12, Ca3La2Sn3S12, and Ca3Er2Sn3s12 are prepared from appropriate mixtures of CaS, SrS, La2S3, Er2S3, SnS2, Sn, S, La, or Y using KBr as fluxing agent (silica ampules, 950—1000 °C, 100—316 h).

A highly efficient procedure becomes possible by the use of paraformaldehyde under conditions A).

The structures of the new title compounds (IV) (triclinic, space group P, Z = 2) and (VI) (P, Z = 2) are determined by single crystal XRD.

Cephalosol (1), a potent antimicrobial secondary metabolite with a new carbon skeleton, was characterized from the culture of Cephalosporium acremonium IFB-E007 that used to reside as an endophyte in Trachelospermum jasminoides (Apocynaceae). Its structure and absolute configuration were unambiguously determined by spectroscopic and computational approaches.