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A cascade oxidative cyclization reaction for the synthesis of chromone derivatives was developed by using LiO tBu as a mediator and air as an oxidant. The reaction was carried out without the assistance of a transition metal under mild conditions to afford the chromones in good yields with high regioselectivities. [ABSTRACT FROM AUTHOR]

Lithium makes it possible: The enantioselective Michael addition of aldehydes to nitroalkenes was catalyzed by the readily available proline lithium salt. Remarkably, the asymmetric Michael reaction was scaled up to 50 mmol with 23:1 d.r. and 90 % ee. [ABSTRACT FROM AUTHOR]

Synthesize while the iron is hot: The synthesis of 2 ‐ vinylquinolines via a FeCl3 ‐ catalyzed CH sp3 functionalization and a subsequent CN cleavage is reported. The method is simple and efficient, and avoids the use of organometallic compounds. A variety of 2 ‐ vinylquinolines were obtained from readily available 2 ‐ methylquinolines with moderate to good yields. [ABSTRACT FROM AUTHOR]

A highly anti-selective asymmetric Henry reaction has been developed, affording synthetically versatile β-nitroalcohols in a predominately anti-selective manner (mostly above 15:1) and excellent ee values (mostly above 95 %). Moreover, the anti-selective Henry reaction was carried out in the presence of water for the first time with up to 99 % ee. The catalytic mechanism was proposed based on the detection of the intermediates by extractive electrospray ionization mass spectrometry (EESI-MS). Furthermore, the anti adducts have been successfully transformed into the biochemically important (+)-spisulosine and a pyrroloisoquinoline derivative. [ABSTRACT FROM AUTHOR]

An efficient electrochemical synthesis of carbonyl compounds and homoallylic alcohols was developed in excellent yields using a simple home-made cell. The catalytic redox behavior of the electrode surface and the reaction mechanism was investigated by cyclic voltammetry (CV). [ABSTRACT FROM AUTHOR]

An efficient three-component coupling reaction of alkyne, aldehyde, and amine was carried out in one pot smoothly under the catalysis of AgNO3 and microwave irradiation. The scope of reaction substrates was extended. Moreover, the reaction can be performed under solvent-free condition, affording propargylamine derivatives with high yields. [ABSTRACT FROM AUTHOR]

Cover Feature: Stereoselective Copper-Catalyzed Direct Aldol Reaction of , -Unsaturated -Ketoesters with Coumaran-3-Ones (Chem. Eur. J. 2/2021) Keywords: asymmetric catalysis; coumaran-3-one; direct aldol reaction; Lewis acids; , -unsaturated -ketoesters EN asymmetric catalysis coumaran-3-one direct aldol reaction Lewis acids , -unsaturated -ketoesters 461 461 1 01/09/21 20210107 NES 210107 B A practical approach to access chiral tertiary alcohol skeletons b and biologically important chiral coumaran-3-one derivatives is depicted in the cover artwork. Asymmetric catalysis, coumaran-3-one, direct aldol reaction, Lewis acids, , -unsaturated -ketoesters. [Extracted from the article]

Direct electrochemical synthesis of sulfonyl amidines from aliphatic amines and sulfonyl azides was realized with good to excellent yields. Traditional tertiary amine substrates were broadened to secondary and primary amines. The reaction intermediates were observed and a reaction mechanism was proposed and discussed. [ABSTRACT FROM AUTHOR]

An asymmetric Michael/hemiketalization reaction between isatin-derived β,γ-unsaturated α-ketoesters and 4-hydroxycoumarins was developed in aqueous media. A series of chiral spirooxindole derivatives with an all-carbon quaternary stereogenic center were obtained in high yields (up to 93%) and excellent enantioselectivities (up to 98%). [ABSTRACT FROM AUTHOR]

An asymmetric allylation and allenylation of isatins with facile organoboron reagents was developed under the catalysis of a Lewis acid. A series of optically pure 3-allyl-3-hydroxyoxindoles and 3-allenyl-3-hydroxyoxindoles can be obtained in excellent yields (up to 99% yield) and high enantioselectivities (up to 97% ee). The possible transition state was supported by DFT calculation and the corresponding mechanism was proposed. A gram scale experiment and further functionalization of these chiral 3-hydroxyoxindoles are established. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Under the catalysis of chiral Cu(II) complex, C2 and C3 alkylation of pyrrole and C3 alkylation of indole were realized simultaneously. The chiral oxindole skeleton with an all‐carbon quaternary stereogenic center at the C3‐position could be obtained exclusively with high yields (up to 95%) and excellent enantioselectivities (up to > 99%). [ABSTRACT FROM AUTHOR]

An efficient iodine-mediated electrochemical C(sp3)–H cyclization was developed under mild conditions. A variety of functionalized quinazolinone-fused N-heterocycles can be obtained with good to excellent yields by virtue of this method. The reaction features a broad substrate scope and scalability, and is metal-free and chemical oxidant-free. [ABSTRACT FROM AUTHOR]

Enantioselective Mukaiyama 1,2 addition of silyl enol ethers with oxindolyl β,γ‐unsaturated α‐keto esters was developed under catalysis of a chiral L−Cu complex. The reaction was carried out rapidly under mild conditions, to give rise to a series of chiral β‐hydroxyl carbonyl compounds bearing oxindolyl backbone skeleton with high yields and excellent enantioselectivities, up to 99 %, as well as moderate to great diastereoselectivities, up to >20 : 1. This method provided an elegant synthesis route for the synthesis of such compounds. [ABSTRACT FROM AUTHOR]

An efficient direct aldol reaction between coumaran‐3‐ones and β, γ‐unsaturated α‐ketoesters by virtue of a chiral copper complex is developed. A series of coumaran‐3‐one derivatives containing chiral tertiary alcohol structures are obtained in excellent yields and stereoselectivities. [ABSTRACT FROM AUTHOR]

A series of Schiff-based ligands consisting of both tertiary amines and lipophilic groups were designed and synthesized. Using these ligands, a new chiral surfactant-type metallomicellar catalyst was developed in water, and this was identified by SEM/TEM analyses. These metallomicelles can be empolyed in asymmetric Michael addition reactions in water, delivering the corresponding adducts with excellent yields and enantioselectivities. [ABSTRACT FROM AUTHOR]

A highly enantioselective Mukaiyama aldol reaction of silyl enol ethers with isatins catalyzed by chiral copper complexes was developed. A series of chiral 3-substituted 3-hydroxy-2-oxindoles bearing a tetra-substituted center could be obtained exclusively with high yields (up to 95%) and excellent enantioselectivities (up to 99%). In particular, water was essential to improve the diastereoselectivity. [ABSTRACT FROM AUTHOR]