Organocatalytic Asymmetric Synthesis of o-Carboranyl Amines

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Янв. 14, 2025

Carboranyl amines are distinct from typical organic amines. Due to the electronic influence of carborane cage, they have low nucleophilicity and reluctant alkylate. Moreover, asymmetric synthesis chiral carboranes is still in its infancy. Herein we achieved first catalytic N-alkylation o-carboranyl amine, providing general access diverse secondary with high efficiency enantioselectivity under mild conditions. For time, organocatalysis was introduced chemistry. Key success use situ generated (naphtho-)quinone methides as alkylating reagents suitable acid catalysts. This protocol also applicable S-alkylation 1-SH-o-C2B10H11. Control experiments kinetic studies provided important insights into reaction mechanism, which likely involves rate-determining generation quinone methide followed by fast enantio-determining nucleophilic addition.

Язык: Английский

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Boron cluster organocatalysis

Chem, Год журнала: 2024, Номер 10(1), С. 29 - 32

Опубликована: Янв. 1, 2024

Язык: Английский

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Triborane (B₃H₇)-mediated regioselective substitution reactions of pyridine derivatives

Chemical Science, Год журнала: 2024, Номер 15(34), С. 13923 - 13929

Опубликована: Янв. 1, 2024

There exists an interplay between borane and a Lewis base in their adducts. However, studies on these adducts so far have mainly focused the different reactions of B-H bonds with limited attention given to influence chemistry base, except for BF

Язык: Английский

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Late-Stage Halogenation of Complex Substrates with Readily Available Halogenating Reagents

Accounts of Chemical Research, Год журнала: 2024, Номер 57(21), С. 3161 - 3181

Опубликована: Сен. 20, 2024

ConspectusLate-stage halogenation, targeting specific positions in complex substrates, has gained significant attention due to its potential for diversifying and functionalizing molecules such as natural products pharmaceutical intermediates. Utilizing readily available halogenating reagents, hydrogen halides (HX), N-halosuccinimides (NXS), dichloroethane (DCE) reagents late-stage halogenation shows great promise expanding the toolbox of synthetic chemists. However, reactivity haleniums (X

Язык: Английский

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Boosting 2000‐Fold Hypergolic Ignition Rate of Carborane by Substitutes Migration in Metal Clusters

Advanced Science, Год журнала: 2024, Номер 11(23)

Опубликована: Апрель 3, 2024

Abstract Hypergolic propellants rely on fuel and oxidizer that spontaneously ignite upon contact, which fulfill a wide variety of mission roles in launch vehicles spacecraft. Energy‐rich carboranes are promising hypergolic fuels, but triggering their energy release is quite difficult because ultrastable aromatic cage structure. To steer the development carborane‐based high‐performance material, carboranylthiolated compounds integrated with atomically precise copper clusters presented, yielding two distinct isomers, Cu 14B‐S 14C‐S , both possessing similar ligands core structures. With migration thiolate groups from carbon atoms to boron atoms, ignition delay (ID) time shortened 6870 3 ms when contacted environmentally benign high‐test peroxide (HTP, H 2 O concentration 90%). The extraordinarily short ID ranking among best HTP‐active materials. experimental theoretical findings reveal benefitting groups, characterized by an electron‐rich metal kernel, displays enhanced reducibility superior charge transfer efficiency. This results exceptional activation rates HTP, consequently inducing carborane combustion simultaneous energy. fundamental investigation shed light advanced green propulsion systems.

Язык: Английский

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Palladium-Catalyzed Cross-Coupling Reactions of Carboranes with Alkenes via Selective B–H Bond Activation

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Фев. 17, 2025

A palladium-catalyzed Heck-type cross-coupling reaction of carboranes with alkenes in 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) was realized. This shows good B(9) selectivity for m-carboranes and is also suitable o- p-carborane. Meanwhile, a series mono-, di-, trisubstituted were compatible substrates to afford the alkenylated products 16–89% yields. The 1,2-bis(carboranyl)ethylene first synthesized by vinyltrimethylsilane m-carborane. Further transformations C═C bond product examined hydroboration oxidation, hydroboration, bromination generate corresponding B(9)-functionalized m-carboranes.

Язык: Английский

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Dual activation with Fe(NTf2)3 and I2: regioselective halogenation of aromatic compounds using N-halosuccinimides (NXS)

Tetrahedron, Год журнала: 2025, Номер unknown, С. 134544 - 134544

Опубликована: Фев. 1, 2025

Язык: Английский

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Zwitterionic Dual Halogen Bond-Catalyzed Electrophilic Bromination of Electron-Deficient Arenes under Mild Conditions

ACS Catalysis, Год журнала: 2025, Номер unknown, С. 4270 - 4279

Опубликована: Фев. 25, 2025

Язык: Английский

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Palladium-Catalyzed Selective B(3)-Esterification of o-Carboranes with CO and Alcohols

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Март 3, 2025

Selective functionalization of o-carboranes has received tremendous attention, specifically in the regioselective modification ten chemically similar BH vertices within o-carborane cage. We disclose herein a strategy for palladium-catalyzed esterification B(3)-H bond using tungsten hexacarbonyl as carbon monoxide source. The corresponding functionalized were prepared moderate to very good yields with excellent regioselectivity.

Язык: Английский

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Designing Peptide-Based Nucleophilic Catalysts Possessing Multiple Identical Active Sites for Late-Stage Chlorination of Peptides and Drugs

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Апрель 3, 2025

In the quest for developing catalysts with multiple active sites, we designed a series of methionine-based peptide prepared by classical coupling. Given widespread presence aromatic chloro-substituents and their significant pharmacokinetic properties, performance these were evaluated late-stage chlorination tyrosine residue on peptides up to octamer as well drug molecules. The operationally simple reaction conditions, excellent catalyst loading 0.25 mol %, gram-scale reactions are major highlights this method.

Язык: Английский

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