Introduction to Radical Coupling

Addition of electron-donating 1-azidoadamantane (N3Ad) to 16-Cp* generated a dimeric product, [Cp*U(NAd)(MesHPDIMe)]2 (18), from radical coupling at the para-pyridine position of the pyridine(diimine) ligand and H-atom abstraction, formed through a monomeric intermediate that was observed in solution but could not be isolated.

Mechanistic studies show that the radical coupling of the heteroaryl radical and sulfur dioxide radical anion may be the key step during the reaction process, as supported by EPR spectroscopy and DFT calculations.

Aliphatic aldehydes were decarbonylated into 1°, 2° and 3° alkyl radicals at low temperature which subsequently allows the cascade construction of C(sp3)–C(sp3) and C(sp3)–O bonds via radical insertion and radical–radical coupling.

The contribution of radical coupling and substitution in overall degradation decreased in the order of p-ASA > 2-APAA > 4-HPAA > ROX, which resulted from the varying reactivity and steric hindrance of the substituents.

Here, we have successfully demonstrated the use of ketyl radicals in intermolecular cross radical–radical coupling, which has opened a different door for accessing complex tertiary alcohols.

We show that, contrary to the notion that radical coupling reactions are usually barr.

The transformation of synthesized alkenylindiums by iodination, radical coupling, and Pd-catalyzed cross-coupling successfully afforded trisubstituted enamines with high regio- and stereoselectivities.

From difunctionalization of a single alkene to radical-dual-difunctionalization of two different alkenes! Abundant aliphatic aldehydes were readily decarbonylated into alkyl radicals for the cascade construction of C(sp3)-C(sp3), C(sp3)-C(sp3) and C(sp3)-O bonds via double radical addition and radical-radical coupling, following the intrinsic nucleophilic/electrophilic reactivity of both the radicals and alkenes.

A formation pathway is suggested which includes the formation of a caffeic acid ortho-quinone followed by a Michael-type reaction, and radical coupling of a semiquinone of the formed dimer and a third caffeic acid molecule.

A Cu-catalyzed synthesis of 1,2-thiobenzonitriles via oxidative C-N cleavage of 3-aminoindazoles followed by radical coupling with thiols is developed.

In this transformation, a radical coupling pathway is proposed with the insertion of sulfur dioxide in the presence of a photocatalyst under visible light irradiation.

In the case of the halogens, either direct photochemical generation of X˙ followed by radical–radical coupling with H3C˙ yields the XCH3 product, or the intervention of transition metal halides which permit radical halogen-transfer from such species as FeX2+ find utility for photosynthesis of XCH3.

A major BPA oxidation product, 4-hydroxycumyl alcohol (HCA), is formed through radical coupling, and was therefore used as a metric for polymer production in this study.

Laccase enzyme was used to oxidize lignosulfonates resulting in the formation of phenoxyl radicals that reacted with NH2 groups SucCTS either through radical coupling or Michaeĺs addition.

Ambient temperature is sufficient for the formation of the reactive radicals, and the site-selectivity can be switched from C2 to C4 by changing the radical coupling sources.

Hydroxystilbene glucosides, particularly isorhapontin and astringin, are incorporated into Norway spruce bark lignin and participate in radical coupling reactions during lignification.

A practical and efficient Lewis acid-catalyzed radical–radical coupling reaction of N-hydroxyphthalimide esters and 4-cyanopyridines with inexpensive bis(pinacolato)diboron as reductant has been de.

Biphenolic compounds were synthetized by radical coupling and then anchored on alumina by microwave assisted process.

Significant oxyl radical character in the RuV-oxo unit is experimentally demonstrated by radical coupling reactions between the oxo cubane and both 2,4,6-tri-tert-butylphenoxyl and trityl radicals.

It first serves as a HAT initiator and subsequently functions as a silyl radical stabilizing group, which is critical to highly selective cross-radical coupling.

Kinetic analysis suggests water oxidation at a single site of Ru where O-O bond formation occurs via radical-radical coupling pathway between the oxygen atom of ruthenium-oxo species and the oxygen atom of the hydroxocerium(IV) ion.

A simple and efficient visible-light mediated synthesis of thiosulfonates via a radical-radical coupling of sulfenyl radicals and arylsulfonyl radicals was developed.

Homolytic photocleavage of internal S–S bonds creates thiyl groups close to each other, driving an increased kinetic feasibility for the cyclization reaction by radical coupling.

This contribution introduces a straightforward method for preparing well-defined polymeric nanoparticles using radical coupling process of ketyl moieties resulted from triplet excitation of pendant benzophenone groups.

This protocol utilized a radical addition/radical coupling sequence, allowing for facile and regioselective installation of versatile β-azido pyridines under redox-neutral and mild conditions.

A radical coupling process is indicated and a mechanism with a Ni(I)-Ni(III) catalytic cycle is proposed.

Instead, a radical-radical coupling process between a boryl phosphonium pyridyl radical and a boryl-stabilized cyanopyridine radical explains the C-C bond-forming step.

In the presence of radical trap vinylcyclopropane (VCP) the relative distributions of polysulfane speciation are relatively unaffected, suggesting that radical coupling is not a dominant pathway.

Aldehydes were homolytically cleavaged to produce acyl radicals and subsequently allowed for the successive construction of C(sp2)-C(sp3), C(sp3)-C(sp3), and C(sp3)-O bonds via dual radical insertions and radical-radical coupling, following the intrinsic nucleo/electrophilic reactivity of both the radicals and alkenes.

Consequently, the N−O bond formation does not follow a radical coupling mechanism proposed for the N−N bond formation but is accomplished by three mutual electron‐transfer pathways between 2 and the O atom donor, thanks to the ambiphilic nature of 2.

It has been observed that mixed reactions of hydrolysis and homolysis are involved, but the SEL is mainly cleaved homolytically, favoring recondensation through radical coupling even at low reaction severity.

In general, the singlet diradicals are quite short-lived because of the fast radical-radical coupling reactions.

Radical-radical couplings are mostly nearly diffusion controlled processes.

In this study, a green approach combining enzyme-initiated reversible addition-fragmentation chain transfer (RAFT) polymerization and free-radical coupling was developed for the modification of jute fiber, which is a typical lignin-based cellulose.

Possible reaction pathways could be attributable to four CPO-mediated processes, including bromination, radical coupling, intramolecular cyclization and debromination.

Cross-linking between hemicelluloses and lignin occurs via two different mechanisms: incorporation into lignin by radical coupling of ferulate substitutions on xylan in commelinid monocots, and incorporation of hemicellulosic glycosyl residues by re-aromatisation of lignification intermediates.

The electron separation effect induced by attraction of positive charges originating from protonation is proposed to explain the diradicalization, which is different from the traditional radical-coupler-radical coupling mode.