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It is still a challenge to construct single-atom level reduction and oxidation sites in single-component photocatalyst by manipulating coordination configuration for photocatalytic water splitting. Herein, the atomically dispersed asymmetric configuration of six-coordinated Co-S 2 O 4 (two exposed S atoms, two OH groups, and two Co─O─Zn bonds) suspending on ZnIn 2 S 4 nanosheets verified by combining experimental analysis with theoretical calculation, is applied into photocatalytic water splitting. The Co-S 2 O 4 site immobilized by Vs acts as oxidation sites to guide electrons transferring to neighboring independent S atom, achieving efficient separation of reduction and oxidation sites. It is worth mentioning that stabilized Co-S 2 O 4 configuration show dynamic structure evolution to highly active Co-S 1 O 4 configuration (one exposed S atom, one OH group, and three Co─O─Zn bonds) in reaction, which lowers energy barrier of transition state for H 2 O activization. Ultimately, the optimized photocatalyst exhibits excellent photocatalytic activity for water splitting (H 2 : 80.13 µmol g -1 h -1 , O 2 : 37.81 µmol g -1 h -1 ) and outstanding stability than that of multicomponent photocatalysts due to dynamic and reversible evolution between stable Co-S 2 O 4 configuration and active Co-S 1 O 4 configuration. This work demonstrates new cognitions on immobilized strategy through vacancy inducing, manipulating coordination configuration, and dynamic evolution mechanism of single-atom level catalytic site in photocatalytic water splitting., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

A new palladium-catalyzed reductive [5+1] cycloaddition of 3-acetoxy-1,4-enynes with CO, enabled by hydrosilanes, has been developed for delivering valuable functionalized phenols. This methodology employs hydrosilanes as the external reagent to facilitate the [5+1] carbonylative benzannulation. The reaction is a conceptually and mechanistically novel carbonylative cycloaddition route for the construction of substituted phenols, through the formation of four new chemical bonds, with excellent functional-group tolerance., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

α-Carbonyl alkyl bromides are powerful reactive species for the formation of carbon-carbon bonds. Strategies relying on intermolecular C-H functionalization and cross-coupling reactions, also referred to as intramolecular cyclization, have been employed for the construction of alkenes, alkanes, ketones, and other natural-product-like ring compounds from simple alkynes, alkenes, and 1,n-enynes. In view of the importance of these α-carbonyl alkyl bromides, especially the difluoro carbonyl alkyl bromides, many researchers have focused their efforts to develop facile and mild synthetic methods for compounds with important biological activities. This review aims to briefly discuss the latest developments in the transformation of α-carbonyl alkyl bromides with emphasis on the related reaction mechanisms., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The first iron-catalyzed 1,2-difunctionalization of styrenes and conjugated alkenes with silanes and either N or C, using an oxidative radical strategy, is described. Employing FeCl 2 and di-tert-butyl peroxide allows divergent alkene 1,2-difunctionalizations, including 1,2-aminosilylation, 1,2-arylsilylation, and 1,2-alkylsilylation, which rely on a wide range of nucleophiles, namely, amines, amides, indoles, pyrroles, and 1,3-dicarbonyls, thus providing a powerful platform for producing diverse silicon-containing alkanes., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new FeCl3 and BF3 ⋅OEt2 co-catalyzed tandem hetero-[5+2] cycloaddition of 2-(2-aminoethyl)oxiranes with a wide range of alkynes, including terminal alkynes and alkyl-substituted internal alkynes is presented. This is the first example of rapid and facile production of diverse 2,3-dihydro-1H-azepines through a sequence of epoxide ring-opening, annulation, and dehydroxylation with broad substrate scope and exquisite selectivity control., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new iron-facilitated silver-mediated radical 1,2-alkylarylation of styrenes with α-carbonyl alkyl bromides and indoles is described, and two new C-C bonds were generated in a single step through a sequence of intermolecular C(sp(3)-Br functionalization and C(sp(2))-H functionalization across the alkenes. This method provides an efficient access to alkylated indoles with broad substrate scope and excellent selectivity., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new metal-free oxidative radical [2+2+1] carbocyclization of benzene-linked 1,n-enynes with two C(sp(3))-H bonds adjacent to the same heteroatom is described. This method achieves two C(sp(3))-H oxidative functionalizations and an annulation, thus providing efficient and general access to a variety of fused five-membered carbocyclic hydrocarbons., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A rhodium(III)-catalyzed [3+2]/[5+2] annulation of 4-aryl 1-tosyl-1,2,3-triazoles with internal alkynes is presented. This transformation provides straightforward access to indeno[1,7-cd]azepine architectures through a sequence involving the formation of a rhodium(III) azavinyl carbene, dual C(sp(2))-H functionalization, and [3+2]/[5+2] annulation., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new metal-free radical 5-exo-dig cyclization of phenol-linked 1,6-enynes with O2, 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO), and tBuONO is described. With this general method, carbonylated benzofurans can be accessed through incorporation of two oxygen atoms into the product from O2 and TEMPO through dioxygen activation and oxidative cleavage of the N-O bond, respectively., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

This study describes a new rhodium(III)-catalyzed [3+2] annulation of 5-aryl-2,3-dihydro-1H-pyrroles with internal alkynes using a Cu(OAc)2 oxidant for building a spirocyclic ring system, which includes the functionalization of an aryl C(sp(2))-H bond and addition/protonolysis of an alkene C=C bond. This method is applicable to a wide range of 5-aryl-2,3-dihydro-1H-pyrroles and internal alkynes, and results in the assembly of the spiro[indene-1,2'-pyrrolidine] architectures in good yields with excellent regioselectivities., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Here we describe the one-pot construction of the pyrrolo[4,3,2-de]quinolinone scaffold by a cascade nitration/cyclization sequence of 1,7-enynes with tBuONO and H2O. The cascade proceeds through alkene nitration, 1,7-enyne 6-exo-trig cyclization, C-H nitrations, and redox cyclization, and exhibits excellent functional group tolerance. The mechanism was investigated using in situ high-resolution mass spectrometry (HR-MS)., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The oxidative interception of various σ-alkyl palladium(II) intermediates with additional reagents for the difunctionalization of alkenes is an important research area. A new palladium-catalyzed oxidative difunctionalization reaction of alkenes with α-carbonyl alkyl bromides is described, in which the σ-alkyl palladium(II) intermediate is generated through a Heck insertion and trapped using an aryl C(sp(2))-H bond. This method can be applied to various α-carbonyl alkyl bromides, including primary, secondary, and tertiary α-bromoalkyl esters, ketones, and amides., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A practical method for the synthesis of azepine derivatives, a typical seven-membered heterocyclic ring system, was developed and involves the use of hexafluoroantimonic acid to catalyze a formal [3+2+2] cycloaddition of aziridines with two alkynes. This method was applicable to two of the same or different terminal alkynes for the [3+2+2] cycloaddition with unactivated aziridines, and furnished the corresponding azepine derivatives in good yields with good levels of chemo- and regioselectivity. The mechanism was also discussed according to the results of the in situ HRMS and (1)H NMR analysis., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A mild and general alkylation of terminal alkynes with transient σ-alkylpalladium(II) complexes for assembling alkyl-substituted alkynes is described. This method represents a new way to the use of transient σ-alkylpalladium(II) complexes in organic synthesis through 1,2-carboalkynylation of alkenes., (Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Open a new door: The first example of alkene synthesis from alkyl electrophiles with Grignard reagents using the Kumada cross-coupling reaction strategy is reported. This method opens a new door for the Kumada cross-coupling reaction, allowing alkenes to be prepared from the reaction of tosylalkanes with Grignard reagents., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Keeping options open: the new and mild title reaction involving indoles selectively furnishes 1 and 2 with the aid of tert-butyl hydroperoxide (TBHP). The method represents the first example of a copper-catalyzed α arylation of α-amino carbonyl substrates leading to α-aryl α-imino and α-aryl α-oxo carbonyl compounds using a C-H oxidation strategy., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)