Main Group Redox Catalysis of Organopnictogens: Vertical Periodic Trends and Emerging Opportunities in Group 15

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(4), P. 1699 - 1721

Published: Jan. 19, 2021

A growing number of organopnictogen redox catalytic methods have emerged-especially within the past 10 years-that leverage plentiful reversible two-electron chemistry Group 15. The goal this Perspective is to provide readers context understand dramatic developments in catalysis over decade with an eye toward future development. An exposition fundamental differences atomic structure and bonding pnictogens, thus molecular electronic compounds, presented establish backdrop against which reactivity-and ultimately catalysis-is framed. deep appreciation these underlying periodic principles informs understanding differing modes evokes key challenges field moving forward. We close by addressing forward-looking directions likely animate area years come. What new manifolds can be developed through creative catalyst reaction design that take advantage intrinsic reactivity pnictogens drive discoveries catalysis?

Language: Английский

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Bismuth Redox Catalysis: An Emerging Main-Group Platform for Organic Synthesis

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(2), P. 1382 - 1393

Published: Jan. 7, 2022

Bismuth has recently been shown to be able maneuver between different oxidation states, enabling access unique redox cycles that can harnessed in the context of organic synthesis. Indeed, various catalytic Bi platforms have discovered and revealed emerging opportunities field main group catalysis. The goal this perspective is provide an overview synthetic methodologies developed date, which capitalize on cycling. Recent methods via low-valent Bi(II)/Bi(III), Bi(I)/Bi(III), high-valent Bi(III)/Bi(V) couples are covered as well their underlying mechanisms key intermediates. In addition, we illustrate design strategies stabilizing bismuth species, highlight characteristic reactivity complexes, compared lighter p-block d-block elements. Although it not catalysis nature, also discuss a recent example non-Lewis acid, redox-neutral Bi(III) proceeding through organometallic steps. We close by discussing future directions hope Perspective will chemists with guiding principles for development transformations employing bismuth.

Language: Английский

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Synthesis and isolation of a triplet bismuthinidene with a quenched magnetic response

Science, Journal Year: 2023, Volume and Issue: 380(6649), P. 1043 - 1048

Published: May 18, 2023

Large spin-orbit coupling (SOC) is an intrinsic property of the heavy elements that directly affects electronic structures compounds. In this work, we report synthesis and characterization a monocoordinate bismuthinidene features rigid bulky ligand. All magnetic measurements [superconducting quantum interference device (SQUID), nuclear resonance (NMR)] point to diamagnetic compound. However, multiconfigurational chemical calculations predict ground state compound be dominated (76%) by spin triplet. The apparent diamagnetism explained extremely large SOC-induced positive zero-field splitting more than 4500 wavenumbers leaves M S = 0 sublevel thermally isolated in state.

Language: Английский

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Catalytic Hydrodefluorination via Oxidative Addition, Ligand Metathesis, and Reductive Elimination at Bi(I)/Bi(III) Centers

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(32), P. 12487 - 12493

Published: Aug. 6, 2021

Herein, we report a hydrodefluorination reaction of polyfluoroarenes catalyzed by bismuthinidenes, Phebox-Bi(I) and OMe-Phebox-Bi(I). Mechanistic studies on the elementary steps support Bi(I)/Bi(III) redox cycle that comprises C(sp2)–F oxidative addition, F/H ligand metathesis, C(sp2)–H reductive elimination. Isolation characterization cationic Phebox-Bi(III)(4-tetrafluoropyridyl) triflate manifests feasible addition into bond. Spectroscopic evidence was provided for formation transient hydride during catalysis, which decomposes at low temperature to afford corresponding bond while regenerating propagating Phebox-Bi(I). This protocol represents distinct catalytic example where main-group center performs three organometallic in low-valent manifold.

Language: Английский

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Redox-Neutral Organometallic Elementary Steps at Bismuth: Catalytic Synthesis of Aryl Sulfonyl Fluorides

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(51), P. 21497 - 21502

Published: Dec. 16, 2021

A Bi-catalyzed synthesis of sulfonyl fluorides from the corresponding (hetero)aryl boronic acids is presented. We demonstrate that organobismuth(III) catalysts bearing a bis-aryl sulfone ligand backbone revolve through different canonical organometallic steps within catalytic cycle without modifying oxidation state. All have been validated, including insertion SO2 into Bi-C bonds, leading to structurally unique O-bound bismuth sulfinate complex. The protocol affords excellent yields for wide range aryl and heteroaryl acids, displaying functional group tolerance.

Language: Английский

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Molecular bismuth(iii) monocations: structure, bonding, reactivity, and catalysis

Chemical Communications, Journal Year: 2021, Volume and Issue: 57(37), P. 4483 - 4495

Published: Jan. 1, 2021

Structurally defined, molecular bismuth(iii) cations show remarkable properties in coordination chemistry, Lewis acidity, and redox allowing for unique applications synthetic chemistry.

Language: Английский

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Radical Activation of N–H and O–H Bonds at Bismuth(II)

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(36), P. 16535 - 16544

Published: Sept. 2, 2022

The development of unconventional strategies for the activation ammonia (NH3) and water (H2O) is capital importance advancement sustainable chemical strategies. Herein we provide synthesis characterization a radical equilibrium complex based on bismuth featuring an extremely weak Bi–O bond, which permits in situ generation reactive Bi(II) species. ensuing organobismuth(II) engages with various amines alcohols exerts unprecedented effect onto X–H leading to low BDFEX–H. As result, N–H O–H bonds─including water─occurs seconds at room temperature, delivering well-defined Bi(III)-amido -alkoxy complexes. Moreover, demonstrate that resulting Bi(III)–N complexes engage unique reactivity pattern triad H+, H–, H• sources, thus providing alternative pathways main group chemistry.

Language: Английский

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Bi-Catalyzed Trifluoromethylation of C(sp²)–H Bonds under Light

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(47), P. 25538 - 25544

Published: Nov. 14, 2023

We disclose a Bi-catalyzed C–H trifluoromethylation of (hetero)arenes using CF3SO2Cl under light irradiation. The catalytic method permits the direct functionalization various heterocycles bearing distinct functional groups. structural and computational studies suggest that process occurs through an open-shell redox manifold at bismuth, comprising three unusual elementary steps for main group element. cycle starts with rapid oxidative addition to low-valent Bi(I) catalyst, followed by light-induced homolysis Bi(III)–O bond generate trifluoromethyl radical upon extrusion SO2, is closed hydrogen-atom transfer Bi(II) intermediate.

Language: Английский

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Bismuth in Radical Chemistry and Catalysis

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 63(8)

Published: Nov. 22, 2023

Abstract Whereas indications of radical reactivity in bismuth compounds can be traced back to the 19 th century, preparation and characterization both transient persistent bismuth‐radical species has only been established recent decades. These advancements led emergence field chemistry, mirroring progress seen for other main‐group elements. The seminal fundamental studies this area have ultimately paved way development catalytic methodologies involving intermediates, a promising approach that remains largely untapped broad landscape synthetic organic chemistry. In review, we delve into milestones eventually present state‐of‐the‐art Our focus aims at outlining intrinsic discoveries inorganic/organometallic chemistry contextualizing their practical applications synthesis catalysis.

Language: Английский

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Small molecule activation by well-defined compounds of heavy p-block elements

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(52), P. 8043 - 8058

Published: Jan. 1, 2023

Recent advances in the activation of small molecules with well-defined molecular compounds heavy p-block elements (with a principle quantum number n > 4) are summarized, highlighting key strategies, challenges, and opportunities.

Language: Английский

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