Transition-Metal-Catalyzed C–H Bond Activation for the Formation of C–C Bonds in Complex Molecules

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(12), P. 7692 - 7760

Published: May 10, 2023

Site-predictable and chemoselective C–H bond functionalization reactions offer synthetically powerful strategies for the step-economic diversification of both feedstock fine chemicals. Many transition-metal-catalyzed methods have emerged selective activation bonds. However, challenges regio- chemoselectivity with application to highly complex molecules bearing significant functional group density diversity. As molecular complexity increases within structures risks catalyst intolerance limited applicability grow number groups potentially Lewis basic heteroatoms. Given abundance bonds already diversified such as pharmaceuticals, natural products, materials, design selection reaction conditions tolerant catalysts has proved critical successful direct functionalization. such, innovations formation carbon–carbon been discovered developed overcome these limitations. This review highlights progress made metal-catalyzed C–C forming including alkylation, methylation, arylation, olefination targets.

Language: Английский

---

One-Shot Construction of BN-Embedded Heptadecacene Framework Exhibiting Ultra-narrowband Green Thermally Activated Delayed Fluorescence

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(21), P. 11504 - 11511

Published: May 16, 2023

BN-embedded nonacene, tridecacene, and heptadecacene frameworks were constructed using one-shot quadruple, sextuple, octuple borylation reactions, respectively. The key to success is the judicious choice of borylating reagents long-chain alkyl-substituted carbazolyl groups as boron-trapping groups, which suppressed decrease in HOMO energy insolubilization associated with borylation. Based on product yields, each electrophilic C-H proceeded >99% yield, best efficiency reported so far for reactions. Owing multiple resonance effects boron nitrogen, prepared acenes exhibited ultra-narrowband green thermally activated delayed fluorescence full-width at half-maximum 12-16 nm; moreover, their kRISC values order 105 s-1. We fabricated an organic light-emitting diode by employing nonacene emitter, high external quantum (EQE) 28.7%. device also showed a minimum roll-off EQE 25.8% 1000 cd m-2.

Language: Английский

---

Transition metal–catalyzed remote C─H borylation: An emerging synthetic tool

Science Advances, Journal Year: 2023, Volume and Issue: 9(16)

Published: April 21, 2023

Transition metal–catalyzed C─H bond activation and borylation is a powerful synthetic method that offers versatile transformation from organoboron compounds to virtually all other functional groups. Compared the ortho-borylation, remote remains more challenging owing inaccessibility of these bonds. Enforcing metal catalyst toward bonds needs well-judged design through proper ligand development. This review article aims summarize recent discoveries for by employment new catalyst/ligand with help steric ligand, noncovalent interactions. It has been found now takes part in total synthesis natural products shorter route. Whereas, Ir-catalyzed predominant, cobalt also started affect this field sustainable cost-effective

Language: Английский

---

Photoelectrochemically driven iron-catalysed C(sp3)−H borylation of alkanes

Nature Synthesis, Journal Year: 2024, Volume and Issue: 3(4), P. 537 - 544

Published: Jan. 31, 2024

Language: Английский

---

Copper-Mediated Dehydrogenative C(sp³)–H Borylation of Alkanes

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(28), P. 15207 - 15217

Published: July 6, 2023

Borylations of inert carbon-hydrogen bonds are highly useful for transforming feedstock chemicals into versatile organoboron reagents. Catalysis these reactions has historically relied on precious-metal complexes, which promote dehydrogenative borylations with diboron reagents under oxidant-free conditions. Recently, photoinduced radical-mediated involving hydrogen atom transfer pathways have emerged as attractive alternatives because they provide complimentary regioselectivities and proceed metal-free However, net oxidative processes require stoichiometric oxidants therefore cannot compete the high economy their precious-metal-catalyzed counterparts. Herein, we report that CuCl2 catalyzes radical-mediated, C(sp3)-H alkanes bis(catecholato)diboron This is a result an unexpected dual role copper catalyst, promotes oxidation reagent to generate electrophilic bis-boryloxide acts effective borylating agent in subsequent redox-neutral photocatalytic C-H borylations.

Language: Английский

---

Dual-Ligand Catalyst for the Nondirected C–H Olefination of Heteroarenes

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(14), P. 8198 - 8208

Published: March 28, 2023

Pd(II)-catalyzed nondirected C-H functionalization of heteroarenes is a significant challenge for the following reasons: poor reactivity electron-deficient heterocycles and unproductive coordination Lewis basic nitrogen atoms. Existing methodologies using palladium catalysis often employ large excess heterocycle substrates to overcome these hurdles. Despite recent advances in arenes that allow them be used as limiting reagents, reaction conditions are incompatible with heteroarenes. Herein we report dual-ligand catalyst enables olefination without substrate. In general, use 1-2 equiv was sufficient obtain synthetically useful yields. The rationalized by synergy between two types ligands: bidentate pyridine-pyridone ligand promotes cleavage; monodentate substrate acts second form cationic Pd(II) complex has high affinity arenes. proposed cooperation supported combination X-ray, kinetics, control experiments.

Language: Английский

---

Simple Ether‐Directed Enantioselective C(sp³)−H Borylation of Cyclopropanes Enabled by Iridium Catalysis

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(14)

Published: Feb. 10, 2023

Reported here is an efficient and simple ether-directed iridium-catalyzed enantioselective C(sp3 )-H borylation of cyclopropanes. Various functional groups were well-tolerated, affording a vast array chiral cyclopropanes with high enantioselectivities. We also demonstrated that the turnover numbers current reaction could be up to 335.

Language: Английский

---

Selective Methane Oxidation by Heterogenized Iridium Catalysts

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(2), P. 769 - 773

Published: Jan. 3, 2023

Oxidative methane (CH4) carbonylation promises a direct route to the synthesis of value-added oxygenates such as acetic acid (CH3COOH). Here, we report strategy realize oxidative CH4 through immobilized Ir complexes on an oxide support. Our immobilization approach not only enables activation but also allows for easy separation and reutilization catalyst. Furthermore, show that key step, methyl migration, forms C–C bond, is sensitive electrophilicity carbonyl, which can be tuned by gentle reduction centers. While as-prepared catalyst mainly featured Ir(IV) preferred CH3COOH production, reduced featuring predominantly Ir(III) led significant increase CH3OH production at expense yield CH3COOH.

Language: Английский

---

Noncovalent interaction with a spirobipyridine ligand enables efficient iridium-catalyzed C–H activation

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: April 17, 2024

Abstract Exploitation of noncovalent interactions for recognition an organic substrate has received much attention the design metal catalysts in synthesis. The CH–π interaction is especially interest molecular because both C–H bonds and π electrons are fundamental properties molecules. However, their weak nature, these have been less utilized control reactions. We show here that can be used to kinetically accelerate catalytic activation arenes by directly recognizing π-electrons arene substrates with a spirobipyridine ligand. Computation ligand kinetic isotope effect study provide evidence between backbone substrate. rational exploitation will open new avenues catalysis.

Language: Английский

---

Photocatalytic Direct Borylation of Benzothiazole Heterocycles via a Triplet Activation Strategy

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 11, 2025

Boron compounds are widely employed in organic chemistry, pharmaceuticals, and materials science. Among them, borylated heterocycles serve as versatile synthons for the construction of new C-C or C-heteroatom bonds via coupling radical processes. Such methods direct C-H borylation reactions high synthetic value to reduce number steps amount waste improve efficiency. Despite significant advances, remains an ongoing challenge with great potential applications chemical synthesis. Herein, we describe a photocatalytic reaction five-membered ring by employing stable N-heterocyclic carbene borane borylating reagent photoredox catalyst. Under green mild conditions, was achieved on series benzo-fused heterocyclic compounds. Further studies demonstrate utility this approach pharmaceutical agrochemical research.

Language: Английский

---