In-silico-assisted derivatization of triarylboranes for the catalytic reductive functionalization of aniline-derived amino acids and peptides with H2

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

Published: May 7, 2024

Cheminformatics-based machine learning (ML) has been employed to determine optimal reaction conditions, including catalyst structures, in the field of synthetic chemistry. However, such ML-focused strategies have remained largely unexplored context catalytic molecular transformations using Lewis-acidic main-group elements, probably due absence a candidate library and effective guidelines (parameters) for prediction activity elements. Here, construction triarylborane its application an ML-assisted approach reductive alkylation aniline-derived amino acids C-terminal-protected peptides with aldehydes H

Language: Английский

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Monodentate σ-Accepting Boron-Based Ligands Bearing Square-Planar Ni(0) Centers

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

Published: Feb. 28, 2025

Transition metals are known to work as electron donors toward electron-accepting heavier-group-13 elements (Al, Ga, and In), called Z-type ligands. However, complexes with boron-based ligands stable only in the presence of additional coordination units (the so-called "supported-ligand" strategy). Here, we report synthesis characterization square-planar Ni(0) that bear tris(perfluoroaryl)boranes monodentate ligands, even though such geometry has been traditionally associated Ni(II) species based on well-established ligand-field theory. A combined theoretical experimental approach revealed a mixed covalent/dative character for Ni–B bonds. This strategy uses frustrated L/Z-ligand pairs combine sterically encumbered electron-donating (L-type) form noncovalent interactions over L–M–Z achieve unprecedented low-valent transition metal

Language: Английский

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Recent Trends in Triarylborane Chemistry: Diversification of Structures and Reactivity via meta-Substitution of the Aryl Groups

Synthesis, Journal Year: 2024, Volume and Issue: 56(22), P. 3421 - 3430

Published: Aug. 19, 2024

Abstract This Short Review summarizes the synthesis and applications of triarylboranes (BAr3), including both homoleptic heteroleptic species, with a focus on modification their electronic structural properties via introduction meta-substituents respect to B atoms Ar groups. approach constitutes complementary alternative conventional strategies for design BAr3, which are usually based ortho- and/or para-substituents. An initial analysis revealed that CH3 F most common in hitherto reported BAr3 (apart from H atom). Thus, an extensive exploration other substituents, e.g., heavier halogens, longer or functionalized alkyl groups, aryl will increase our knowledge structure reactivity eventually lead range new applications. 1 Introduction 2 Scope this 2.1 The Electronic Steric Influence meta-Substituents 2.2 Molecular Transformations Mediated by meta-Substituted Boranes 2.3 Other Examples meta-Functionalization 3 Conclusions Perspectives

Language: Английский

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Boosting Turnover in the Triarylborane-Catalyzed Hydrogenation of N-Substituted Indoles via Olefin-to-Nitrogen Lewis Base Switching in H₂-Cleavage Steps

Precision Chemistry, Journal Year: 2024, Volume and Issue: 3(3), P. 128 - 134

Published: Dec. 18, 2024

The shelf-stable heteroleptic borane B(2,6-Cl2C6H3)(3,5-Br2-2,6-F2C6H)2 (B7) efficiently catalyzes the solvent-free hydrogenation of various substituted indoles to indolines with an unprecedented turnover number 8,500, which is more than 400-fold higher that reported for B(C6F5)3 under diluted conditions. Mechanistic studies revealed this proceeds via olefin-to-nitrogen switching Lewis bases involved in H2-cleavage steps: initially, H2 cleavage mediated by a frustrated pair (FLP) comprising indole C3-carbon and boron atoms, then switches FLP system indoline nitrogen atoms after formation indoline. This study demonstrates potential relatively benign main-group elements catalytic synthesis valuable N-containing molecules using H2.

Language: Английский

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Strategic use of crude H2 for the catalytic reduction of carbonyl compounds

Tetrahedron Chem, Journal Year: 2023, Volume and Issue: 9, P. 100059 - 100059

Published: Dec. 23, 2023

Toward a more efficient use of crude H2 without its energy-consuming purification, this study employs gaseous mixtures H2, CO, CO2, and CH4 for the catalytic hydrogenation aldehydes ketones in presence strategically designed triarylboranes 4-methyltetrahydropyrane as greener ethereal solvent. The present results emphasize unexplored utility less-toxic main-group catalysis using H2. This stands contrast to well-established transition-metal that generally requires purified

Language: Английский

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In-Silico-Assisted Derivatization of Triarylboranes for the Catalytic Reductive Functionalization of Amino Acids with H2

Published: Nov. 3, 2023

Cheminformatics-based machine learning (ML) has assisted in determining optimal reaction conditions, including catalyst struc-tures, the field of synthetic chemistry. However, such ML-focused strategies have remained largely unexplored context catalytic molecular transformations using Lewis-acidic main-group elements, probably due to absence a candidate library and effective guidelines (parameters) for prediction activity elements. Here, construction triarylborane its application an ML-assisted approach reductive alkylation amino acids with aldehydes H2 is reported. The obtained results suggest that deformation energy serves as useful parameter Gauss-ian process regression construct adequate models predicting turnover frequencies triarylboranes under applied model while Gaussian progress based on levels lowest unoccupied orbitals (LUMOs) empty p-orbitals boron tend underestimate frequency. borane, i.e., B(2,3,5,6-Cl4-C6H)(2,6-F2-3,5-(CF3)2-C6H)2, effectively catalyzes functionalization aniline-derived C-terminal-protected peptides presence 4-methyltetrahydropyrane H2, generating H2O sole by-product.

Language: Английский

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Triarylborane Catalysis: From Hydrogenation of Unsaturated Molecules to H₂ Purification

Journal of Synthetic Organic Chemistry Japan, Journal Year: 2024, Volume and Issue: 82(11), P. 1097 - 1106

Published: Nov. 1, 2024

Herein we summarize our recent progress on the design, synthesis, and catalytic application of triarylboranes. We demonstrated that structurally well-characterized triarylboranes catalyzed hydrogenation N-heteroaromatics carbonyl compounds when crude H2 (a mixture H2, CO, CO2, CH4) was directly used as reductant. In addition, proposed a concept 'remote back strain' to finely tune Lewis acidity by regulating stability base-borane adducts via an intramolecular repulsion between meta-substituents aryl groups. Such approaches were eventually combined with machine learning efficiently assisted optimization boranes reductive alkylation multiply-substituted aniline derivatives, including amino acids peptides, using These results manifest new aspect main-group catalysis beyond its simple alternative well-established transition metal-catalyzed processes.

Language: Английский

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Effective Synthesis of 1,4-Diarylbutadienes via Reductive Desulfonylation of 1,3-Butadienyl Sulfones by Proper Choice of Regioisomeric π-Expanded Pyrene Photocatalysts

Bulletin of the Chemical Society of Japan, Journal Year: 2023, Volume and Issue: 97(2)

Published: Dec. 1, 2023

Abstract For the reductive desulfonylation of 1,3-butadienyl sulfones, we synthesized 1,3,6,8-tetra(phenylethynyl)pyrenes possessing (S)-citronellyloxy groups on terminal phenyl rings at ortho-, meta-, and para-positions to serve as photocatalysts. All these pyrenes exhibited catalytic activity in butadienyl sulfones when exposed either green (514 nm) or blue LEDs (447 presence sacrificial reducing agent i-Pr2NEt. The photocatalytic activities compounds could be fine-tuned by altering position group. Under illumination, ortho-(S)-citronellyloxy pyrene photocatalyst (S)-1 proved most effective 1,4-diphenylbutadien-1-yl sulfone 4b produce 1,4-diphenylbutadiene (5b) with an 88% yield. On other hand, 1,2-diphenyethen-1-yl 4a, para-(S)-citronellyloxy (S)-3 demonstrated high performance, producing stilbene (5a) a 92% Furthermore, trio photocatalysts highly efficient promoting functionalized dienyl well π-expanded sulfones. By judiciously selecting suitable from (S)-1-3, reactions rapidly effectively accomplished.

Language: Английский

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