P–P Coupling with and without Terminal Metal–Phosphorus Intermediates

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 28, 2025

Terminal metal–phosphorus (M–P) complexes are of significant contemporary interest as potential platforms for P-atom transfer (PAT) chemistry. Decarbonylation metal–phosphaethynolate (M–PCO) has emerged a general synthetic approach to terminal M–P complexes. that stabilized by strong multiple bonds kinetically persistent and isolable. In the absence stabilization, formation diphosphorus-bridged (i.e., M–P–P–M species) is often interpreted evidence intermediacy reactive, unobserved species. Here, we demonstrate while diphosphorus can arise from reactive species, P–P coupling also proceed directly M–PCO species without Photochemical decarbonylations pincer-supported Ni (II)–PCO complex at 77 K afford spectroscopically observed Ni–P complex, which best described triplet, Ni(II)-metallophosphinidene with two unpaired electrons localized on atomic phosphorus ligand. Thermal annealing this transient results in rapid dimerization corresponding P22–-bridged dinickel complex. Unexpectedly, same be accessed via thermally promoted process light. The analysis reaction kinetics, isotope-labeling studies, computational indicate thermal proceeds noncanonical mechanism avoids intermediates. Together, these represent first observation characterized intermediates not required obtain products. These observations provide critical mechanistic understanding activation modes relevant transfer.

Language: Английский

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Chiral Cp^xRhodium(III)‐Catalyzed Enantioselective Aziridination of Unactivated Terminal Alkenes

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(12)

Published: Jan. 27, 2024

Chiral cyclopentadienyl-rhodium(III) Cp

Language: Английский

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Precision single-atom editing: new frontiers in nitrogen insertion and substitution for the generation of N-heterocycles

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(14), P. 4041 - 4053

Published: Jan. 1, 2024

This paper primarily focuses on the editing of nitrogen atoms, encompassing insertion N, substitution C with and utilization 15 N in place 14 for construction N-heterocycles.

Language: Английский

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Photoinduced Metallonitrene Formation by N₂ Elimination from Azide Diradical Ligands

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(42)

Published: Aug. 7, 2023

Transition-metal nitrides/nitrenes are highly promising reagents for catalytic nitrogen-atom-transfer reactivity. They typically prepared in situ upon optically induced N2 elimination from azido precursors. A full exploitation of their potential, however, requires in-depth knowledge the primary photo-induced processes and structural/electronic factors mediating loss with birth terminal metal-nitrogen core. Using femtosecond infrared spectroscopy, we elucidate here molecular-level mechanisms responsible formation a unique platinum(II) nitrene triplet ground state closed-shell azide precursor. The spectroscopic data combination quantum-chemical calculations provide compelling evidence that product initial occupation singlet excited an anionic diradical ligand is bound to low-spin d8 -configured PtII ion. Subsequent intersystem crossing generates Pt-bound diradical, which smoothly evolves into via near barrierless adiabatic dissociation. Our highlight importance productive, -releasing possessing ππ* character as design principle accessing efficient N-atom-transfer catalysts.

Language: Английский

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An Open-Shell Fe^IV Nitrido

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 19, 2025

We report the photogeneration and characterization of an open-shell, terminal iron nitrido (EmL)Fe(N) using a sterically encumbered dipyrrin ligand environment. The Fe–N distance in solid-state, zero-field 57Fe Mössbauer spectrum, computational analysis are consistent with triplet electronic ground state nitrido. Notably, attenuation multiple bond character through occupying π*Fe–N enables (i) primary C(sp3)–H amination, (ii) H2 cleavage, (iii) aromatic C–C (iv) photocatalytic N-atom transfer reactivity. These modes reactivity have not previously been observed low-spin Fe(N) analogues.

Language: Английский

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Nitrene-mediated Aminative N–N–N Coupling: Facile Access to Triazene 1-Oxides

Chemical Science, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

A nitrene-mediated aminative N–N–N coupling enables direct triazene 1-oxide synthesis via an aminonitrene–nitrosoarene pathway.

Language: Английский

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Iron-nickel alloy particles with N-doped carbon “armor” as a highly selective and long-lasting catalyst for the synthesis of N-benzylaniline molecules

Nano Research, Journal Year: 2023, Volume and Issue: 17(4), P. 2308 - 2319

Published: Sept. 8, 2023

Language: Английский

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Bonding and Reactivity of d⁰ Transition Metal Imido Complexes Encoded in Their ¹⁵N NMR Signatures

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(14), P. 9860 - 9870

Published: March 27, 2024

Terminal imido complexes containing metal–nitrogen multiple bonds have been widely used in organometallic chemistry and homogeneous catalysis. The role of terminal ligands spans from reactive sites to spectator motifs, largely depending on the nature metal center its specific coordination sphere. Aiming at identifying reactivity descriptors for M–N bonds, we herein explore solid-state 15N NMR spectroscopy (ssNMR) early transition augmented by computational studies show that asymmetry parameter, κ (skew, 1 ≥ −1), readily available experiments or calculations, is diagnostic complexes. While inert exhibit skew values (κ) close 1, highly moieties display significantly lower (κ ≪ 1) as found metallocene bis-imido Natural chemical shielding analysis shows away are associated with an asymmetric development π-orbitals around bond moiety, a larger double-bond character imido. Notably, this descriptor does not directly relate M–N–C angle, illustrating shortcoming evaluating bonding hybridization geometrical parameters alone. Overall, enables obtain direct experimental evidence π-loading effect seen bis(imido) related complexes, thus explaining their bonding/reactivity.

Language: Английский

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Diversification of Naphthol Skeletons Triggered by Aminative Dearomatization

Organic Letters, Journal Year: 2024, Volume and Issue: 26(23), P. 4910 - 4915

Published: May 31, 2024

A silver-catalyzed aminative dearomatization of naphthols has been developed and integrated into a stepwise approach for subsequent skeletal diversifications including ring expansion, opening, contraction, atom transmutation aryl scaffolds. This enables the synthesis diverse array azepinones, unsaturated amides, isoquinolines, indenones from naphthol substrates. Its application in bioactive functional molecules as well conversion complex molecular skeletons underscores its broad potential applicability. Mechanistic investigations suggest intermediacy dearomatized intermediates.

Language: Английский

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Bonding and Reactivity of d0 Transition Metal Imido Complexes Encoded in their 15N NMR Signatures

Published: March 4, 2024

Terminal imido complexes, containing metal-nitrogen multiple bonds, have been widely used in organometallic chemistry and homogeneous catalysis. The role of terminal ligands span from reactive site to spectator motif, largely depending on the nature metal center its specific coordination sphere. Aiming at identifying reactivity descriptors for M-N we herein explore solid-state 15N NMR spectroscopy (ssNMR) early-transition complexes augmented by computational studies show that asymmetry parameter k, (skew, 1 ≥ k -1), readily available experiments or calculations, is diagnostic bonds complexes. While inert exhibit skew values (k) close 1, highly moieties display significantly lower (k << 1) as found metallocene bis-imido Natural Chemical Shielding analysis shows away are associated with an asymmetric development pi orbitals around bond moiety, a larger sp2-hybridized character nitrogen. Notably, this descriptor does not directly relate M-N-C angle, illustrating shortcoming evaluating hydridization geometrical parameters alone. Overall, enables obtain direct experimental evidence pi-loading effect seen bis(imido) related thus explaining their reactivity.

Language: Английский

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