N-Heterocyclic carbene-catalyzed enantioselective synthesis of planar-chiral cyclophanes via dynamic kinetic resolution DOI Creative Commons
Jiayan Li, Ziyang Dong, Chen Yang

et al.

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

Published: March 15, 2024

Abstract Planar-chiral cyclophanes have gained considerable concerns for drug discovery due to their unique conformational strain and 3D structure. However, the enantioselective synthesis of planar-chiral is a long-standing challenge synthetic community. We herein describe an N-heterocyclic carbene (NHC)-catalyzed asymmetric construction cyclophanes. This transformation occurs through dynamic kinetic resolution (DKR) process convert racemic substrates into macrocycle scaffolds in good high yields with excellent enantioselectivities. The ansa chain length aromatic ring substituent size crucial achieve DKR approach. Controlled experiments DFT calculations were performed clarify process.

Language: Английский

Catalytic atroposelective synthesis of axially chiral benzonitriles via chirality control during bond dissociation and CN group formation DOI Creative Commons

Ya Lv,

Guoyong Luo, Qian Liu

et al.

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: Jan. 10, 2022

Abstract The applications of axially chiral benzonitriles and their derivatives remain mostly unexplored due to synthetic difficulties. Here we disclose an unusual strategy for atroposelective access via formation the nitrile unit on biaryl scaffolds pre-installed with stereogenic axes in racemic forms. Our method starts 2-arylbenzaldehydes sulfonamides as substrates N-heterocyclic carbenes organocatalysts afford good excellent yields enantioselectivities. DFT calculations suggest that loss p -toluenesulfinate group is both rate-determining stereo-determining step. axial chirality controlled during bond dissociation CN formation. reaction features a dynamic kinetic resolution process modulated by covalent non-covalent catalytic interactions. from our can be easily converted large set functional molecules show promising activities chemical syntheses anti-bacterial plant protections.

Language: Английский

Citations

62
Dual Catalysis Relay: Coupling of Aldehydes and Alkenes Enabled by Visible-Light and NHC-Catalyzed Cross-Double C–H Functionalizations DOI
Ming‐Shang Liu,

Lin Min,

Bi-Hong Chen

et al.

ACS Catalysis, Journal Year: 2021, Volume and Issue: 11(15), P. 9715 - 9721

Published: July 19, 2021

Direct functionalizations of two distinct inert C–H bonds represent the most ideal ways to construct C–C bonds. Herein, we report an intermolecular vinylation aldehydes using alkenes as vinylating reagents through sequential two-fold functionalizations. The merging visible light and N-heterocyclic carbene catalysis allows for coupling with a dual relay enabled cross-dehydrogenative mechanism. use diphenoquinone is essential success this reaction, which plays intriguing role in electron acceptor well radical reservoir enabling forming process.

Language: Английский

Citations

60
Generation of azolium dienolates as versatile nucleophilic synthonsvia N-heterocyclic carbene catalysis DOI
Jian Gao, Jie Feng, Ding Du

et al.

Organic Chemistry Frontiers, Journal Year: 2021, Volume and Issue: 8(21), P. 6138 - 6166

Published: Jan. 1, 2021

The recent advances in N -heterocyclic carbene (NHC)-catalyzed generation of azolium dienolates from different precursors and their synthetic applications for the construction various valuable molecules are summarized comprehensively this review.

Language: Английский

Citations

58
Stereodivergent propargylic alkylation of enals via cooperative NHC and copper catalysis DOI Creative Commons

Yu‐Hua Wen,

Zijing Zhang, Shuai Li

et al.

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: March 15, 2022

Abstract Despite that asymmetric stereodivergent synthesis has experienced great success to provide unusual processes for the creation of chirality complexity, concepts appliable catalysis are still limited. The dependence on capacity each catalyst precisely control reactive site planar in region poses unparalleled constraints this field. Here, we first demonstrate chiral Cu-allenylidene species can participate propargylic alkylation enals, concert with N-heterocyclic carbenes (NHCs). Thus, all four stereoisomers were obtained excellent enantioselectivity and diastereoselectivity (up >99% e.e. >95:5 d.r.) from same starting materials by simply altering Cu-Pybox complex NHC combinations. rich chemistry workable products enables structurally diverse functional molecules holds potential alkaloid synthesis, as showcased preparation key building block access (-)-perophoramidine.

Language: Английский

Citations

57
Diastereoselective Radical Aminoacylation of Olefins through N-Heterocyclic Carbene Catalysis DOI

Wen-Deng Liu,

Woojin Lee,

Hanyu Shu

et al.

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(49), P. 22767 - 22777

Published: Nov. 24, 2022

There have been significant advancements in radical-mediated reactions through covalent-based organocatalysis. Here, we present the generation of iminyl and amidyl radicals via N-heterocyclic carbene (NHC) catalysis, enabling diastereoselective aminoacylation trisubstituted alkenes. Different from photoredox single electron transfer deprotonated Breslow intermediate to O-aryl hydroxylamine generates an NHC-bound ketyl radical, which undergoes diastereocontrolled cross-coupling with prochiral C-centered radical. This operationally simple method provides a straightforward access variety pyrroline oxazolidinone heterocycles vicinal stereocenters (77 examples, up >19:1 d.r.). Electrochemical studies acyl thiazolium salts support our reaction design highlight reducing ability Breslow-type derivatives. A detailed computational analysis this organocatalytic system suggests that radical–radical coupling is rate-determining step, π–π stacking interaction between radical intermediates subtly controls diastereoselectivity.

Language: Английский

Citations

56
Atroposelective Synthesis of Triaryl α‐Pyranones with 1,2‐Diaxes by N‐Heterocyclic Carbene Organocatalysis DOI
Simiao Zhang, Xiaoxue Wang, Lili Han

et al.

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(52)

Published: Oct. 31, 2022

Atropisomers bearing multiple stereogenic axes are of increasing importance to the field material science, pharmaceuticals, and catalysis. However, atroposelective construction multi-axis atropisomers remains rare challenging, due intrinsical difficulties in stereo-control axes. Herein, we demonstrate a single-step new class 1,2-diaxially chiral triaryl α-pyranones by an N-heterocyclic carbene organocatalytic asymmetric [3+3] annulation well-designed alkynyl acylazolium precursors enolizable sterically hindered 2-aryl ketones. The protocol features broad substrate scope (>50 examples), excellent (most cases >20 : 1 dr, up 99.5 0.5 er), potentially useful synthetic applications. success this reaction relies on rational design structurally matched partners careful selection catalytic system. DFT calculations have also been performed discover rationalize origin high stereoselectivity reaction.

Language: Английский

Citations

54
Access to Planar Chiral Ferrocenes via N-Heterocyclic Carbene-Catalyzed Enantioselective Desymmetrization Reactions DOI

Xiaokang Lv,

Jun Xu,

Cuiyun Sun

et al.

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(4), P. 2706 - 2713

Published: Feb. 9, 2022

Ferrocene-derived dicarbaldehydes bearing pro-chiral planes are desymmetrized under the catalysis of chiral N-heterocyclic carbene organic catalysts. The reaction features selective activation and one aldehyde moieties ferrocene derivative while leaving other unit untouched. Our affords enantiomerically enriched planar products obtained that amenable for further transformations. Preliminary application studies show encouraging results when our explored in chemical synthesis antimicrobial utilities pesticide development.

Language: Английский

Citations

46
N-Heterocyclic-Carbene-Catalyzed C–H Acylation via Radical Relay DOI
Yunquan Man, Shiwen Liu, Bo Xu

et al.

Organic Letters, Journal Year: 2022, Volume and Issue: 24(3), P. 944 - 948

Published: Jan. 20, 2022

A method of N-fluorocarboxamide-directed N-heterocyclic-carbene (NHC)-catalyzed benzylic C-H acylation with aldehydes via the hydrogen atom transfer strategy is disclosed. This transformation involves a sequence single-electron transfer, 1,5-hydrogen and radical cross-coupling steps. offers facile access to various highly functionalized ketones exhibits good chemical yields functional group tolerance.

Language: Английский

Citations

43
Enantioselective Synthesis of C−O Axially Chiral Diaryl Ethers by NHC‐Catalyzed Atroposelective Desymmetrization** DOI
Sayan Shee,

Sowmya Shree Ranganathappa,

Mahesh S. Gadhave

et al.

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(52)

Published: Nov. 21, 2023

Axially chiral diaryl ethers, a distinguished class of atropisomers possessing unique dual C-O axis, hold immense potential for diverse research domains. In contrast to the catalytic enantioselective synthesis conventional single axis bearing atropisomers, atroposelective axially ethers containing flexible remains significant challenge. Herein, we demonstrate first N-heterocyclic carbene (NHC)-catalyzed via esterification dialdehyde-containing ethers. Mechanistically, reaction proceeds NHC-catalyzed desymmetrization strategy afford corresponding ether in good yields and high enantioselectivities under mild conditions. The derivatization synthesized product expands utility present access library compounds. temperature dependency preliminary investigations on racemization barrier bonds are also presented.

Language: Английский

Citations

40
Oxidative N‐Heterocyclic Carbene Catalysis DOI Creative Commons
Carmela De Risi, Arianna Brandolese, Graziano Di Carmine

et al.

Chemistry - A European Journal, Journal Year: 2022, Volume and Issue: 29(4)

Published: Oct. 7, 2022

N-Heterocyclic carbene (NHC) catalysis is a by now consolidated organocatalytic platform for number of synthetic (asymmetric) transformations via diverse reaction modes/intermediates. In addition to the typical umpolung processes involving acyl anion/homoenolate equivalent species, implementation protocols under oxidative conditions greatly expands possibilities this methodology. Oxidative NHC-catalysis allows and oxygenative through specific manipulations Breslow-type species depending upon oxidant used (external or O

Language: Английский

Citations

39