Themed collection 2023 Organic Chemistry Frontiers HOT articles

Ligand relay catalysis, which brings a new way to broaden the SMMLC strategy, has recently been developed and discussed. This strategy acts as a powerful way, broadening the range of catalytic transformations to construct highly functional molecules.

Directing group-assisted selective C–H bond activation of six-membered N-heterocycles and benzo-fused N-heterocycles has been reported.

Molecules with spiro-linked π-conjugated structures have attracted considerable attention in the realm of organic functional materials due to their advantageous structural features.

This review focuses on the eight-shaped double ring structure of tetraphenylethylene, summarizes the research progress of structures, ionic molecular structures and metal molecular structures, and looks forward to its future development direction.

This review summarizes the recent progress in borylation driven by BX₃ in the fields of organic synthesis and drug synthesis.

The recent advancements in single-electron nucleophilic organocatalysis that facilitates single-electron transfer between substrates through the formation of a covalent intermediate were summarized based on the type of catalyst.

The recent advances in trifluoroethylation reactions were summarized based on the bond formation: C(sp)–CH₂CF₃, C(sp²)–CH₂CF₃, C(sp³)–CH₂CF₃, and X (X = N, O, S, Se)–CH₂CF₃.

Vinylene carbonate (VC) has emerged as a promising coupling partner to participate in various attractive C–H conversions and implement an increasing number of novel reactions. In this review, we provide a summary of the advancements achieved in metal-catalyzed C–H functionalization using VC.

This review highlights the recent advances in radical acylated difunctionalization of unsaturated carbon–carbon bonds and focuses on the mechanistic insights of these transformations.

Photogenerated ketenes simplify and accelerate the synthesis of diverse cyclic architectures and demonstrate their promising applications in flow chemistry.

This review highlights recent advances in stereoselective carbon–heteroatom bond forming reactions, including C–N, C–O, C–S, C–F, C–P, etc., that were enabled by NHC organocatalysis with a focus on new activation modes and reactive intermediates.

This review summarizes the recently developed photocatalytic strategies for the installation of the formyl group into various scaffolds.

This review will highlight several recent and lesser-reviewed works related to the preparation of chiral nanographenes, specifically focusing on structures prepared by non-Scholl methods.

This review will focus on the electrochemical synthesis of diversified functionalized oxindole derivatives through C-S, C-O, C-C, C-Se, and C-N bond formation over the past decade.

The latest achievements in transition-metal-catalyzed enantioselective defluorinative coupling reactions have been comprehensively summarized on the basis of the classification of transition-metal catalysts.

A summary of the chemical syntheses of bacterial non-2-ulosonic acids and their derivatives via de novo synthetic approaches starting from non-sugar compounds and total synthesis starting from sugar material.

This review summarizes the advances in the field of intramolecular kinetic resolution (KR) mediated by non-enzymatic catalysts. The relative classification of intramolecular KR is accomplished and several categories of reactions are discussed.

The synthetic and mechanistic aspects of the role of the trisulfide radical anion S₃˙⁻ in organic chemistry are reviewed.

This review highlights the recent advances in both electrochemical borylation and hydroboration to synthesize organoboron compounds and electrochemical transformation of organoboron compounds to construct carbon–carbon and carbon–heteroatom bonds.

This review focuses on the very recent advances (from 2020 to the beginning of 2023) in enantioselective catalytic reactions for the construction of oxa-quaternary stereocenters.

This review summarizes a view of the advances in the catalytic asymmetric α-functionalization of vinylogous nucleophilic species, the content of which is categorized based on the type of vinylogous donor.

Recent advances in the electrochemical generation of 1,3-dicarbonyl radicals from C–H bonds and their mechanistic insights and synthetic applications have been summarized.

This review summarizes the recent advances in cyclization reactions involving pyridinium 1,n-zwitterions (n = 4 and 5) and highlights the applications of pyridinium 1,n-zwitterions (n = 4 and 5) in the efficient construction of heterocycles.

The allylation of aldehydes with dienes was achieved using cobalt and chromium catalysts through a metal-hydride hydrogen atom transfer (MHAT) pathway. The novel reaction resulted in the formation of various homo-allyl alcohols with excellent diastereoselectivity.

The first asymmetric total syntheses of (+)-pancratinines B and C and total syntheses of (−)-montanine, (−)-pancracine and (−)-brunsvigine were realized in a divergent fashion. Our synthetic strategy features a copper-catalyzed [3 + 2] annulation reaction and a Pictet–Spengler cyclization.

We report an efficient and versatile catalytic N-heterocyclic nitrenium charge transfer complex strategy for the single-electron reduction of chloroform, resulting in the generation of the dichloromethyl radical for use in various transformations.

A synthetic method that enables the regio- and chemoselective gold(I)-catalysed azo coupling of 1,2- and 1,4-diazoquinones with 1H-indoles to give a wide range of (E)-3-arylazoindoles is reported.

Two unprecedented diterpene heterodimers, isoxerophilins A and B (1 and 2), were isolated from Isodon xerophilus. A bioinspired semisynthesis of ten isoxerophilin analogues was accomplished. Compound 12 exhibited obvious latent tumor immunotherapy activity.

We describe a novel 1,2,2-trifunctionalization of maleimides with 1,7-enynes and oxime esters through simultaneous construction of four C−C bonds and a C≡N bond in one pot based on the radical relay/1,5-hydrogen-atom transfer (HAT).

Twisted D–A TADF triads DI-PF and DI-PI based on a diindolocarbazole donor and dibenzo[a,c]phenazine (PF) and phenanthro[9,10-d]imidazole (PI) acceptors were utilized for E–Z photoisomerization of stilbene and C–H arylation of heteroarenes.

A bifunctional squaramide catalyzes the enantioselective arylation of isoxazolin-5-ones with o-quinone diimides (o-QDIs) to give isoxazolin-5-ones featuring an arylated quaternary stereocenter in high yields and excellent enantioselectivities.

A copper(I)-catalyzed highly diastereo- and enantioselective Kinugasa/aldol cascade reaction of N-(2-acylaryl) propiolamides with nitrones has been demonstrated for efficient synthesis of structurally novel chiral spiro β-lactams.

A photoredox-catalyzed direct C(sp²)–H fluoroalkylation of quinoxalin-2(1H)-ones with (fluoroalkyl)triphenylphosphonium salts and alkenes is described, providing a practical approach for the generation of diverse fluoroalkyl-containing quinoxalin-2(1H)-ones.

A green and sustainable electrochemical alternative strategy for the synthesis of biologically important [1,2,4]-triazolo-[3,4-i]-purine derivatives via intramolecular oxidative C–N bond coupling has been established.

An electrochemical multicomponent reaction (e-MCR) enables the green and sustainable preparation of diverse vicinal sulfenyltetrazolation using the readily available unactivated olefins, thiols, azidotrimethylsilane, and acetonitrile.

Asymmetric aza-Morita–Baylis–Hillman reaction involving endocyclic ketimines, tetra-substituted chiral carbon center was achieved.

The development of chemoselective strategies for complex molecules is intrinsically challenging. In this paper, a facile and diversity-oriented access to benzoazepinespiroindolenines is elaborated via Pd-catalyzed highly chemoselective dearomative spirocyclization of Ugi adducts.

A general method for Ir-catalyzed asymmetric hydrogenation of tetrasubstituted α-acylpyrazole-β-alkyl cycloalkenes has been developed, furnishing 1,2-cis substituted carbo- or heterocycles with high yields and excellent enantioselectivities.

A photocatalytic method for desaturative C(sp³)–H amidation of N-phenylpiperidine under external photocatalyst- and transition metal-free conditions.

An NHC-catalyzed benzannulation reaction of enals and β-trifluoromethylenones is developed for the synthesis of benzotrifluorides.

A photo-induced iron-catalyzed strategy that facilitates the transformation of carboxylic acids and hydrocarbons into thioethers and sulfoxides is herein reported.

Sodium camphorsultam enolates are structurally characterized uncovering monomers and dimers; rate studies reveal ionic transition structures and curious solvation effects.

A visible-light-induced alkylamine-facilitated reductive defluoroallylation of difluoromethyl ketones with allylic chlorides is reported, enabling efficient access to α-fluoro alkenylketones with high efficiency.

Mechanism of catalytic desymmetrization of malonic esters have been explored, which provides molecular-level insights on how the ligand-casted chiral scaffolding can be intentionally applied to differentiate symmetrical elements in desymmetrization.

The cleavage of the inert C(sp²)-OMe bond was developed under a metal-free photocatalytic strategy using 4CzIPN as a mild oxidizing photoredox catalyst.

The use of a supramolecular protecting molecular container, whose host-guest properties are under acid–base control, enables the functionalization with high chemo-, regio- and iteroselectivities of polyamines in a one-pot cyclic process.

An unprecedented catalytic sulfonylation strategy has been developed through the redox transformation of β-sulfinyl esters, providing a facile access to axially chiral sulfone-containing styrenes with VQMs in excellent enantioselectivities.

This study proves Wanbin Zhang's finding that weak attractive interactions between substrate and ligand play an important role in metal-catalyzed asymmetric hydrogenations and shows that the dispersion interaction is the major attractive interaction.

A visible-light induced radical cyclization of olefinic amides with easily available N-sulfonylaminopyridinium salts towards iminoisobenzofurans and benzoxazines has been developed.

A novel and highly efficient strategy for the construction of diverse alkenyl sulfoxides via transition metal-free C–S cross-coupling of sulfenate anions with alkenylsulfonium salts is reported.

Artemeriopolides A–D (1–4), four novel cadinane sesquiterpenoid dimers featuring the rare 2-oxaspiro[4.6]undecan-1,7-dione, 2-oxaspiro[4.5]decan-1-one, and 2-oxaspiro[5.5]undecan-1-one ring systems, were isolated from Artemisia eriopoda.

CAT catalyzes the reaction of 1a to generate intermediate INT2, which is a common intermediate to generate final products 2a and 3a.

This report describes the visible-light-induced C–H/COO–H oxidative coupling reaction of 2-arylbenzoic acids to synthesize benzo-3,4-coumarins by using 2,7-dinitrophenanthrene-9,10-dione as a photocatalyst.

The first asymmetric [4 + 1] annulation of oxindole 3-pyridinium salts and hydrazones is realized by using a chiral N,N′-dioxide-Pr(OTf)₃ complex. A range of bioactive chiral pyrazoline-spirooxindoles are obtained in good yields with excellent ee values.

An electrophilic sulfenylation promoted oxidation of alkynes is presented, providing the chemo-, regio- and stereoselective synthesis of α-sulfenylated α,β-unsaturated aldehydes.

A photoredox catalysed 1,3-oxylallylation of aryl cyclopropanes was accomplished by reaction with carboxylic acids and allyl sulfones.

COAP-Pd-catalyzed asymmetric cascade formal [4 + 1] annulation was developed between racemic vinyl benzoxazinones and N-tosylhydrazone sodium salts, affording trans-2,3-disubstituted indolines in good yields with high stereoselectivity.

Carboxylic acid-assisted sterically demanding reductive cross-coupling between cycloalkenyl and alkyl bromides affords all-carbon tetrasubstituted cycloalkenes under mild reaction conditions in good yields.

A new multicomponent copper(I)-catalyzed interrupted click reaction which allows the rapid modular synthesis of multisubstituted triazole sulfides including various medium-sized and macrocycles in one-step from elemental sulfur was reported.

A photocatalytic dehydration method was developed to efficiently convert benzyl alcohols to the corresponding amides.

Despite significant development of the nascent anion–π interactions in recent years, the noncovalent interactions between fluoride ion, a unique anion species, and electron-neutral aromatic rings remain rare and even controversial.

The bis(pentafluorophenyl)borane-catalyzed E-selective isomerization of terminal alkenes to internal alkenes via a hydroboration/retro-hydroboration sequence is reported.

By combining HTE and machine learning technologies, an iridium(I)-catalyzed highly selective O–H bond insertion reaction of carboxylic acids and sulfoxonium ylides was developed, and an extensive reaction space exploration was accomplished.

An efficient tandem Dowd–Beckwith ring expansion/C–H functionalization of tetrahydroisoquinoline (THIQ) is disclosed upon photocatalysis, which provided a unique thought to connect important medium-sized cycloalkanones with THIQs skeletons together.

The transition metal catalyzed cycloaddition reaction is one of the most powerful tools for the construction of carbon- and heterocycles. DFT studies are performed to investigate the mechanism of the Ni-catalyzed intramolecular [4 + 2] cycloaddition.

Visible light-mediated NHC and photoredox co-catalyzed radical 1,2-sulfonylacylation of allenes via cross-coupling between an allyl radical and an NHC-stabilized acyl radical.

Synthesis of β-azido alkylsulfones through a photoredox-catalyzed azido sulfonylation of alkenes with DABCO·(SO₂)₂, trimethylsilyl azide and alkyl thianthrenium salts is developed.

A photo-induced redox cascade reaction has been developed for the chemoselective construction of isoxazolidine derivatives from stable and easily available nitroarenes and amines.

Photo-induced C–H functionalization for divergent synthesis of quinoxalin-2(1H)-one derivatives using H₂O₂ as an oxidant without a photocatalyst.

The in situ generated aminodiborane  (μ-NH₂B₂H₅) using NH₃BH₃ and elemental iodine (I₂) is used for the reduction of carboxamides to amines.