The First Enantiomeric Stereogenic Sulfur‐Chiral Organic Ferroelectric Crystals

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(31)

Опубликована: Июнь 6, 2023

Chiral ferroelectric crystals with intriguing features have attracted great interest and many point or axial chirality based on the stereocarbon been successively developed in recent years. However, stereogenic heteroatomic never documented so far. Here, we discover report a pair of enantiomeric sulfur-chiral single-component organic crystals, Rs -tert-butanesulfinamide (Rs -tBuSA) Ss (Ss through deep understanding chemical design molecular crystals. Both enantiomers adopt chiral-polar group 2 (C2 ) exhibit mirror-image relationships. They undergo high-temperature 432F2-type plastic phase transition around 348 K. The ferroelectricity has well confirmed by hysteresis loops domains. Polarized light microscopy records evolution ferroelastic domains, according fact that is both ferroelastic. very soft characteristics low elastic modulus hardness reveals their excellent mechanical flexibility. This finding indicates first stereosulfur chiral opening up new fertile ground for exploring application prospects.

Язык: Английский

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Sadphos as Adaptive Ligands in Asymmetric Palladium Catalysis

Accounts of Chemical Research, Год журнала: 2024, Номер unknown

Опубликована: Янв. 31, 2024

ConspectusPalladium catalysis, as one of the most important strategies in asymmetric synthesis, has continuously attracted attention organic chemists. With development chiral ligands, increasingly challenging reactions and substantial progress catalysis are being realized.Since 2014, we have focused on exploiting a series sulfinamide phosphine ligands called "Sadphos," including Ming-Phos, Xu-Phos, Xiao-Phos, Xiang-Phos, TY-Phos, PC-Phos, GF-Phos, WJ-Phos. These can be easily prepared two to four steps using commercial materials. new types shown remarkable performance transition-metal-catalyzed reactions, especially Pd-catalyzed transformations. X-ray diffraction analysis, mechanistic studies, density functional theory calculations revealed that Sadphos coordinate with Pd0 PdII species Pd0/P, Pd0/P,S, or PdII/P,O modes.This Account summarizes our recent efforts toward palladium-catalyzed enantioselective ligands. were found privileged very crucial promote by increasing reactivity enantioselectivity. Ming-Phos is an effective ligand coupling intramolecular Heck providing highly trisubstituted allenes, axially anilides, gem-diarylmethine silanes, disubstituted dihydroisoquinolinones. Incorporation electron-rich cyclohexyl group moiety afforded which showed unique effect transformations, reductive Heck, dearomative Mizoroki–Heck, tandem Heck/Suzuki coupling, carboiodination, carboamination, cross-coupling reactions. Using similar strategy, synthesized more electron–rich TY-Phos Xiang-Phos bearing t-butyl 1-adamantyl at P atoms, respectively. Regarding stereoelectronic features, these characteristic best choice satisfy requirements fluoroarylation gem-difluoroalkenes, intermolecular α-arylation aldehydes, carboetherification alkenyl oximes, carboheterofunctionalization 2,3-dihydrofurans. Compared aforementioned attractive features high nucleophilicity originating from CH2PPh2 ortho-substituent side aryl ring, presumably responsible for its efficiency. The Pd/Xiao-Phos catalyst system shows good secondary oxides, affording P-stereogenic products multiple molecular skeletons. modification basic backbone introducing xanthene skeleton motivated us design synthesize monophosphines, named PC-Phos GF-Phos. various arylation sulfenate anions, denitrogenative cyclization benzotriazoles, dearomatization indoles. practicability GF-Phos was validated three-component N-tosylhydrazones, halides, terminal alkynes, well N-tosylhydrazones vinyl iodides pendent amines. In addition, ferrocene-derived WJ-Phos employed Suzuki–Miyaura reaction, biaryl monophosphine oxides excellent enantiomeric excesses.

Язык: Английский

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Copper‐Catalyzed Chemoselective Asymmetric Hydrogenation of C=O Bonds of Exocyclic α,β‐Unsaturated Pentanones

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(35)

Опубликована: Июнь 12, 2023

A highly chemoselective earth-abundant transition metal copper catalyzed asymmetric hydrogenation of C=O bonds exocyclic α,β-unsaturated pentanones was realized using H2 . The desired products were obtained with up to 99 % yield and 96 ee (enantiomeric excess) (99 ee, after recrystallization). corresponding chiral allylic pentanol can be converted into several bioactive molecules. mechanism investigated via deuterium-labelling experiments control experiments, which indicate that the keto-enol isomerization rate substrate is faster than also show Cu-H complex only catalyze chemoselectively reduction carbonyl group. Computational results multiple attractive dispersion interactions (MADI effect) between catalyst bulky substituents play important roles stabilize states reduce generation by-products.

Язык: Английский

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Pd-Catalyzed Asymmetric Aza-Heck Cyclization/Sonogashira Reaction of Alkene-Tethered Oxime Esters and Alkynes

ACS Catalysis, Год журнала: 2024, Номер 14(7), С. 5305 - 5313

Опубликована: Март 26, 2024

Over the past few decades, Narasaka–Heck-type difunctionalization of tethered alkenes has emerged as a powerful strategy to produce heterocyclic scaffolds. However, asymmetric synthesis rarely been explored. Herein, we report robust palladium-catalyzed enantioselective Narasaka–Heck cyclization–Sonogashira reaction alkene-tethered oxime esters and terminal alkynes. By employing new Ming-Phos ligand, obtain high yields pyrrolines with quaternary stereocenter enantioselectivities under mild conditions. Density functional theory (DFT) study reveals weak interaction between aromatic ring substrate fragment naphthyl group in which probably accounts for stereoselectivity.

Язык: Английский

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Recent advances in the metal-catalyzed asymmetric alkene hydrogenation of cyclic conjugated carbonyl compounds

Organic Chemistry Frontiers, Год журнала: 2024, Номер 11(10), С. 2934 - 2953

Опубликована: Янв. 1, 2024

This review summarizes the recent advances (2016–2023) in stereoselective metal-catalyzed hydrogenation of cyclic α,β-unsaturated ketones, lactams and lactones since considerable developments were made. Where possible application these methodologies synthesis is outlined.

Язык: Английский

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Ionic Hydrogen Bond‐Assisted Catalytic Construction of Nitrogen Stereogenic Center via Formal Desymmetrization of Remote Diols

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(31)

Опубликована: Май 15, 2024

The control of noncarbon stereogenic centers is profound importance owing to their enormous interest in bioactive compounds and chiral catalyst or ligand design for enantioselective synthesis. Despite various elegant approaches have been achieved construction S-, P-, Si- B-stereocenters over the past decades, catalyst-controlled strategies govern formation N-stereogenic garnered less attention. Here, we disclose first organocatalytic approach efficient access a wide range nitrogen-stereogenic through desymmetrization approach. Intriguingly, pro-chiral remote diols, which are previously not well addressed with enantiocontrol, differentiated by potent carbene-bound acyl azolium intermediates. Preliminary studies shed insights on critical ionic hydrogen bond (IHB) formed between dimer aggregate diols afford N-oxide products that feature tetrahedral nitrogen as sole element good yields excellent enantioselectivities. Notably, could offer an attractive strategy discovery potential antibacterial agrochemicals.

Язык: Английский

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Application of Asymmetric Catalysis in Chiral Pesticide Active Molecule Synthesis

Journal of Agricultural and Food Chemistry, Год журнала: 2024, Номер 72(31), С. 17153 - 17165

Опубликована: Июль 25, 2024

The different configurations of chiral pesticides generally have significant influence on their biological activities. Chiral agrochemicals with high optical purities become a prominent topic in the research field new due to advantages including lower toxicity, higher efficiency, and reduced residue levels. However, most commercially available that possess elements are still used racemic forms. To date, asymmetric catalysis has emerged as versatile tool for enantioselective synthesis various novel pesticide active molecules. This perspective provides comprehensive overview applications diverse catalytic approaches facile preparation numerous molecules, our own outlook future development this highly direction is also presented at end review.

Язык: Английский

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Unlocking the Asymmetric Hydrogenation of Tetrasubstituted Acyclic Enones

Angewandte Chemie International Edition, Год журнала: 2023, Номер 63(9)

Опубликована: Дек. 14, 2023

Asymmetric hydrogenation (AH) of tetrasubstituted olefins generating two stereocenters is still an open topic. There are only a few reports on the AH with conjugated functional groups, while this process can create useful intermediates for subsequent elaboration relevant end products. Most successfully submitted to belong small number classes; remarkably, acyclic enones represents unsolved challenge. Herein, we disclose class air-stable Ir-P,N catalysts, prepared in three steps from commercially available amino alcohols, that hydrogenate, minutes, wide range electronically and sterically diverse (including exocyclic ones) high yields enantioselectivities. The factors responsible excellent selectivities were elucidated by combining deuterogenation experiments theoretical calculations. calculations indicated reduction follows Ir

Язык: Английский

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Reversal of enantioselectivity by tuning the ring size of ProPhenol

Organic Chemistry Frontiers, Год журнала: 2024, Номер 11(15), С. 4109 - 4118

Опубликована: Янв. 1, 2024

Reported herein is the ligand-ring-size controlled enantiodivergent aza-Friedel–Crafts alkylation reaction of 3-aminophenols with imines.

Язык: Английский

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Asymmetric Transfer Hydrogenation of 3‐Substituted 2H‐1,4‐Benzoxazines under Tethered Cp*Rh(III)‐Diamine Catalysis with Unexpected Reversal of Enantioselectivity

Advanced Synthesis & Catalysis, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 12, 2024

Abstract The asymmetric transfer hydrogenation of 3‐substituted 2 H ‐1,4‐benzoxazines with an azeotropic mixture HCO H/NEt 3 (5/2) using tethered Cp*Rh(III)‐diamine catalysis has been realized. This process allows access to a broad range chiral 3,4‐dihydro‐2 in high yields up 99% ee, and tolerates variety functional groups. enantiocontrol is achieved by the judicious choice catalyst hydrogen source. reaction proceeds unexpected reversal enantioselectivity, which attributed acidic conditions bond between N−H rhodium species O atom substrate.

Язык: Английский

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