Themed collection Organic Synthesis

In this review, we emphasise the importance of the generation of α-boryl carbon-centred radicals and their utilisation in synthesis.

Building on mechanistic perspective, the review intends to demonstrate how the uniqueness of Au-catalysts has realized a myriad of electrophilic functional group transfer reactions with the use of hypervalent iodine(III) reagents over the last decade.

Recent advances in various metal-catalysed asymmetric sequential double hydrofunctionalizations of alkynes have been highlighted in this feature article.

Highlights of the extensive chemistry and applications of bis-pentafluorophenyl borane (“Piers’ borane”) from the 25 years since its first appearance are featured.

Primary amines are one of the most predominant functional groups found in organic molecules. This review covers the most recent developments on photocatalytic deaminative strategies by using Katritzky Salts as alkyl radical reservoirs.

Nitrogen heterocycles are of great medicinal importance, and the construction of nitrogen heterocyclic scaffolds has been one of the focuses in synthetic organic chemistry.

The recently developed annulation reactions using azoalkenes as key intermediates show their great ability to construct diverse types of multi-nitrogen-containing heterocycles. In this feature article, we critically analysed the strategic development and the efficient transformation of azoalkenes to chiral heterocycles and α-functionalized ketone derivatives since 2010.

A general outlook of the changing face of chemical synthesis is provided in this article through recent applications of continuous flow processing in both industry and academia.

An unprecedented CuCl₂-catalysed chemo- and ortho-selective C–H bond functionalization of phenols and naphthols with diazoesters has been developed.

Organocatalysis and highly-polar s-block organometallic chemistry (RLi) work together in water, under air and at room temperature for the selective and ultrafast synthesis of tertiary alcohols.

Alcohol dehydrogenases catalyze the regioselective lactonization of dialdehydes via a bio-Tishchenko-like reaction. The nicotinamide-dependent self-sufficient reduction–oxidation sequence proceeds through a formal intramolecular hydride shift.

We herein report a metal- and solvent-free acetic acid-mediated ring-opening reaction of epoxides with amines.

Asymmetric conjugate addition of PhMe₂SiBPin to a wide range of N-heteroaryl alkenes proceeded in the presence of a copper catalyst coordinated with a chiral phosphoramidite ligand to afford useful β-silyl N-heteroarenes in high yields and ees.

Copper mediated C(sp²)–H amination and hydroxylation of arylphosphinic acid are accomplished by adopting phosphinamide as the directing group.

A palladium-catalyzed, three-component synthesis of imides from feedstock aryl halides, carboxylic acids and isocyanides through the intermediacy of isoimide has been developed.

A palladium-catalyzed exclusively selective alkynylation of indoles has been reported, affording concise access to 7-alkynylindoles from readily available starting materials.

This work reports the first efficient enantioselective intramolecular Buchner reaction of diazoacetamides.

An unprecedented multicomponent reaction involving arynes, allyl bromides, and CO₂ has been developed to construct various allyl o-bromobenzoate scaffolds.

A ruthenium(II)-catalyzed cross-ring (5+1) annulation between 2-aminobiphenyls and activated olefins is disclosed for succinct synthesis of valuable phenanthridine scaffolds.

A Pd-catalyzed decarboxylative cross-coupling of α,β-unsaturated carboxylic acids with cyclic and acyclic epoxides has been developed.

A novel high regio- and diastereo-selectivity reductive functionalization of 1,3-diene has been developed using H₂O as a stoichiometric hydrogen atom donor.

Various neutral, mono- and dicationic halogen bond donors were screened for their ability to act as catalysts in a Nazarov cyclisation reaction.

Dinuclear Co-based catalysts are used for the coupling reaction of epoxides and CO₂ in the presence of a cocatalyst.

A general and highly chemoselective Pd-catalyzed protocol for the synthesis of α,β-unsaturated ketones by carbonylation of vinyl triflates and nonaflates is presented. Applying the specific monophosphine ligand cataCXium® A, the synthesis of various vinyl ketones as well as carbonylated natural product derivatives proceeds in good yields.

The photolysis of donor–acceptor diazoalkanes in the presence of propargylic alcohols furnishes valuable, sterically demanding tetra-substituted cyclopropenes in high yield under metal-free conditions.

A novel Rh-catalysed intermolecular [3+2] cascade cyclization of benzimidates and alkenes has been developed to assemble polysubstituted 3-aminoindenes, which exhibits good functional-group tolerance and excellent regioselectivity.

A direct alkenylation of benzylic C(sp³)–H bonds with diazo compounds with FeCl₂ as the catalyst and DDQ as the oxidant has been developed.

An iridium-catalyzed annulation of chalcones with sulfonyl azides via cascade C–H amidation and aza-Michael addition is developed to provide 2-aryl-2,3-dihydro-4-quinolones.

A new method for the synthesis of furyl-substituted alkenylboronates has been developed by palladium-catalyzed oxidative borylation reaction of conjugated enynones.

One-pot formation of (E)-vinyl silanes and (E)-silyl-substituted α, β-unsaturated amides could be completed easily via palladium carbene migratory insertion in good yields and high chemoselectivity.

We report a new convenient and efficient method utilizing the tropylium ion as a mild and environmentally friendly organocatalyst to mediate retro-Claisen-type reactions.

Aryldiazonium salts and arylboronic acids were coupled via three different pathways from (P,N)–AuCl complexes, with enantiomeric excesses up to 26%.

The C(sp³)–H arylation of benzyl amines with aromatic nitriles for the synthesis of diarylmethylamines was realized without the assistance of transition-metal and photoirradiation.

Here we explore further the use of oxadiazolines, non-stabilised diazo precursors which are bench stable, in direct, non-catalytic, aldehyde C–H functionalisation reactions under UV photolysis in flow and free from additives.

Taking a different route yields the same product of the De Mayo reaction, but allows the use of visible light instead of UV irradiation.

A novel visible-light photocatalytic bicyclization of β-alkynyl propenones with α-bromocarbonyls for highly diastereoselective synthesis of richly decorated syn-fluoren-9-ones is described.

A readily available sulfonium salt opens up new synthetic pathways to access nitrile cyclopropanes in a highly diastereoselective fashion.

This work reports new annulations of N-aryl ynamides with benzisoxazoles to form 6H-indolo[2,3-b]quinoline derivatives.

An asymmetric [2+2] cycloaddition reaction of alkylidene malonates with the internal CC bond of N-allenamides was developed with a Mg(II)/N,N′-dioxide complex as a catalyst.

The asymmetric nucleophilic catalysis by fluoride ions at a carbon-based electrophile has been demonstrated for the first time.

The first general study of aminal radical cyclisations, triggered by reduction of amidines with SmI₂, delivers quinazolinones with complete diastereocontrol.

The stereoselective synthesis of tri-substituted alkenes is challenging.

Triorganoindium reagents can be isolated as bench-stable solid R₃In(DMAP) complexes and show excellent reactivity in palladium-catalyzed cross-coupling reactions.

An unprecedented palladium-catalyzed carbene/alkyne metathesis reaction of alkyne-tethered enynones is described, which delivers fused-furans in moderate to good yields.