Cu-Catalyzed Diastereo- and Enantioselective Synthesis of Borylated Cyclopropanes with Three Contiguous Stereocenters

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

Published: Jan. 17, 2025

Direct synthesis of enantioenriched scaffolds with multiple adjacent stereocenters remains an important yet challenging task. Herein, we describe a highly diastereo- and enantioselective Cu-catalyzed alkylboration cyclopropenes, less reactive alkyl iodides as electrophiles, for the efficient tetra-substituted borylated cyclopropanes bearing three consecutive stereocenters. This protocol features mild conditions, broad substrate scope, good functional group tolerance, affording array chiral in to high yields excellent enantioselectivities. Detailed mechanistic experiments kinetic studies were conducted elucidate reaction pathway rate-determining step reaction. DFT calculations revealed that π···π stacking interaction between phenyl groups on phosphorus ligand, along smaller distortion CuL-Bpin part, contributed The synthetic utility was showcased by facile some valuable centers.

Language: Английский

---

Facile Access to Cyclopropylboronates via Stereospecific Deborylative Cyclization: A Leaving Group‐Assisted Activation of Geminal Diborons

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(21)

Published: March 24, 2023

Herein we reported a transition metal-free deborylative cyclization strategy, based on which two routes have been developed, generating racemic and enantioenriched cyclopropylboronates. The of geminal-bis(boronates) bearing leaving group was highly diastereoselective, tolerating few functional groups applicable to heterocycles. When optically active epoxides were used as the starting materials, cyclopropylboronates could be efficiently prepared with >99 % stereospecificity. Mechanistic studies showed that at γ-position played crucial role significantly promoted activation gem-diboron moiety.

Language: Английский

---

Borylated strain rings synthesis via photorearrangements enabled by energy transfer catalysis

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: April 19, 2025

Language: Английский

---

Enantioselective Suzuki cross-coupling of 1,2-diboryl cyclopropanes

Chemical Science, Journal Year: 2023, Volume and Issue: 14(6), P. 1575 - 1581

Published: Jan. 1, 2023

Herein, we describe the catalytic enantioselective cross-coupling of 1,2-bisboronic esters. Prior work on group specific cross coupling is limited to use geminal bis-boronates. This desymmetrization provides a novel approach prepare enantioenriched cyclopropyl boronates with three contiguous stereocenters, that could be further derivatized through selective functionalization carbon-boron bond. Our results suggest transmetallation, which enantiodetermining step, takes place retention stereochemistry at carbon.

Language: Английский

---

Recent advances in hydrofunctionalisation of cyclopropenes via carbon–heteroatom bond formation

Organic Chemistry Frontiers, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

This review highlights recent advances in the hydrofunctionalisation of cyclopropenes through formation carbon–heteroatom bonds for synthesis polysubstituted cyclopropanes.

Language: Английский

---

Fe-Catalyzed Regioselective C(sp³)–H-Abstraction by Tertiary Cyclopropyl Radicals

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(13), P. 8394 - 8401

Published: June 9, 2023

Tertiary carbon radicals are usually more stable than secondary radicals, and the hydrogen atom transfer (HAT) from C(sp3)–H bonds to tertiary is normally considered be a thermodynamically disfavored pathway. Herein, we disclose an unusual protocol involving functionalization enabled by cyclopropyl radical proceeding through abstraction variety of aliphatic bonds. The reaction can furnish valuable, densely functionalized cyclopropane derivatives. Sufficient mechanistic experiments density functional theory (DFT) calculations have provided theoretical insights into chemo- regioselectivity in this underexplored HAT protocol. method features broad group compatibility high product diversity offers new prospect for functionalization.

Language: Английский

---

Dirhodium(II)-catalyzed enantioselective cyclopropenation of internal alkynes with trifluoromethyl carbene

Chem Catalysis, Journal Year: 2023, Volume and Issue: 3(6), P. 100637 - 100637

Published: May 16, 2023

Language: Английский

---

Copper‐Catalyzed Cyclopropenation of Alkynes with Difluoromethyl Carbene^†

Chinese Journal of Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: April 24, 2025

Comprehensive Summary The [2+1] cycloaddition of alkynes with fluoroalkyl carbenes represents the most straightforward approach for constructing fluoroalkylated cyclopropenes. However, until now, this strategy has not been applicable to difluoromethyl carbene, as its precursor, diazomethane, tends undergo [3+2] form pyrazoles. This study presents first example copper‐catalyzed cyclopropenation employing difluoroacetaldehyde triftosylhydrazone carbene precursor. A wide range internal and terminal alkynes, featuring diverse functional groups, were efficiently converted into corresponding cyclopropenes in good high yields. Mechanistic investigations, supported by DFT calculations, revealed that bulky Tp Br3 Cu(NCMe) catalyst plays a pivotal role facilitating via concerted pathway.

Language: Английский

---

Copper-Catalyzed Dienylation of Aldehydes Using Propargylic Carbonates

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

Published: May 20, 2025

A copper-catalyzed dienylation of aldehydes using propargylic carbonates in the presence B2pin2 has been successfully developed, enabling synthesis a diverse range substituted 1,3-butadienyl-2-carbinols (BDCs). This innovative approach circumvents requirement allene reagents and provides an alternative protocol that allows access to BDCs. In addition, synthetic value products demonstrated series further conversions, reaction mechanism proposed based on control experiments.

Language: Английский

---

Nature-inspired catalytic asymmetric rearrangement of cyclopropylcarbinyl cation

Science Advances, Journal Year: 2023, Volume and Issue: 9(19)

Published: May 10, 2023

In nature, cyclopropylcarbinyl cation is often involved in cationic cascade reactions catalyzed by natural enzymes to produce a great number of structurally diverse substances. However, mimicking this process with artificial organic catalysts remains daunting challenge synthetic chemistry. We report small molecule-catalyzed asymmetric rearrangement cations, leading series chiral homoallylic sulfide products good excellent yields and enantioselectivities (up 99% enantiomeric excess). the presence SPINOL-derived N-triflyl phosphoramide catalyst, dehydration prochiral cyclopropylcarbinols occurs rapidly generate symmetrical which are subsequently trapped thione-containing nucleophiles. A subgram-scale experiment multiple downstream transformations further pursued demonstrate utility. Notably, few heteroaromatic sulfone derivatives could serve as "covalent warhead" enzymatic inhibition severe acute respiratory syndrome coronavirus 2 main protease.

Language: Английский

---