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The Nazarov cyclization reaction is a convenient, widely used method for the synthesis of cyclopentenones. In this account, we reviewed our recent efforts on the chiral proton-transfer shuttle catalysts promoted enantioselective Nazarov cyclization. We have synthesized various chiral cyclopenta[ b ]indoles and chiral α,α′-disubstituted cyclopentenones by means of cooperative catalysis of a Lewis acid and a chiral spiro phosphoric acid. The mechanistic studies revealed that the chiral spiro phosphoric acid acts as a multifunctional catalyst: it co-catalyzes the cyclization of the dienone and enantioselectively catalyzes a proton-transfer reaction of the enol intermediate via a hydrogen--bonding network. 1 Introduction 2 Enantioselective Nazarov Cyclization of Indole Enones 3 Enantioselective Silicon-Directed Nazarov Cyclization 4 Conclusion [ABSTRACT FROM AUTHOR]

Abstract: The transition‐metal‐catalyzed formal C−C bond insertion reaction of diazo compounds with monocarbonyl compounds is well established, but the related reaction of 1,3‐diketones instead gives C−H bond insertion products. Herein, we report a protocol for a gold‐catalyzed formal C−C bond insertion reaction of 2‐aryl‐2‐diazoesters with 1,3‐diketones, which provides efficient access to polycarbonyl compounds with an all‐carbon quaternary center. The aryl ester moiety plays a crucial role in the unusual chemoselectivity, and the addition of a Brønsted acid to the reaction mixture improves the yield of the C−C bond insertion product. A reaction mechanism involving cyclopropanation of a gold carbenoid with an enolate and ring‐opening of the resulting donor–acceptor‐type cyclopropane intermediate is proposed. This mechanism differs from that of the traditional Lewis‐acid‐catalyzed C−C bond insertion reaction of diazo compounds with monocarbonyl compounds, which involves a rearrangement of a zwitterion intermediate as a key step. [ABSTRACT FROM AUTHOR]

A highly enantioselective NH insertion reaction of α-diazoketones was developed by using cooperative catalysis by dirhodium(II) carboxylates and chiral spiro phosphoric acids. The insertion reaction provides a new access route to diverse chiral α-aminoketones, which are versatile building blocks in organic synthesis, with fast reaction rates, good yields and high enantioselectivity under mild and neutral conditions. [ABSTRACT FROM AUTHOR]

An abstract of the article "Enantioselective Iron-Catalyzed Intramolecular Cyclopropanation Reactions" by J.-J. Shen and colleagues is presented.

This is the first asymmetric N-H insertion of α-diazoketones giving α-aminoketones in good yields and with high enantioselectivities. [ABSTRACT FROM AUTHOR]

The article highlights the chemical equations involved in the enantioselective palladium-catalyzed insertion of aryl-diazoacetates into the O-H bonds of phenols.

Chemical formulas showing highly enantioselective S-H bond insertion cooperatively catalyzed by dirhodium complexes and chiral spiro phosphoric acids are presented.

The title methodology allows the preparation of chiral α-substituted carboxylic acids in excellent yields and enantioselectivities. [ABSTRACT FROM AUTHOR]

The synthetic value of this protocol is demonstrated by an efficient preparation of nipecotic acid (VI). [ABSTRACT FROM AUTHOR]

Unsymmetrical peroxides (II) are tested under optimized conditions. [ABSTRACT FROM AUTHOR]

The respective ketone is formed as a by-product in small amounts in most cases. [ABSTRACT FROM AUTHOR]

The carboxy group in the substrates is crucial for this reaction as it acts as an anchor for the Ir-catalysts. [ABSTRACT FROM AUTHOR]

The copper catalyzed cyclization of diazoesters in the presence of a chiral spirobisoxazoline ligand proceeds under mild conditions to give the title compounds with high enantioselectivities. [ABSTRACT FROM AUTHOR]

The copper complexes of chiral spiro phosphoramidite and phosphite ligands were found to be effective catalysts in the asymmetric allylic alkylations of cinnamyl halides with dialkylzincs. The allylic alkylation products were obtained in high regioselectivities (SN2′/SN2 up to 98:2) and enantiomeric excesses of up to 74% for SN2′ products. [Copyright &y& Elsevier]

The title reaction provides a new method for the synthesis of α-diaryl acetates such as (III), (V), and (VII) in good yields and with high enantioselectivities. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Highly Efficient and Practical Hydrogenation of Olefins Catalyzed by in situ Generated Iron Complex Catalysts" published in the periodical "Organic Chemistry Frontiers" in 2015.

A substituent adjacent to the pyridine N atom is crucial to block the coordination ability of the pyridine moiety, an effect which is evidently overturned by the proximate second N atom in substrate (Vb). [ABSTRACT FROM AUTHOR]

The method is extended to the preparation of (VI), the key intermediate for the synthesis of (+)-chelidonine (VII). [ABSTRACT FROM AUTHOR]