Synthesis of Medium-Sized Rings by Z-Retentive Asymmetric Allylic Substitution-Enabled Intermolecular Cascade Cyclization under Iridium/Cinchona Catalysis

ACS Catalysis, Год журнала: 2024, Номер 14(20), С. 15743 - 15750

Опубликована: Окт. 9, 2024

Medium-sized rings are important structural units in organic molecules of significant interest. However, their efficient synthesis, especially a highly enantioselective manner, has been formidable challenge. Herein, we report an synthesis medium-sized aza-rings by Z-retentive asymmetric allylic substitution-enabled intermolecular cascade cyclization via iridium/cinchona dual catalysis. The reaction was performed under mild conditions and with good functional group tolerance. Various nine- to eleven-membered can be afforded moderate high yields (up 98%) enantioselectivities 93% ee). utilization both Z-linear dipole precursor binary catalyst is critical for the desired reactivity.

Язык: Английский

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Iridium-Catalyzed Diastereo- and Enantioselective [4 + 1] Cycloaddition of Hydroxyallyl Anilines with Sulfoxonium Ylides

Organic Letters, Год журнала: 2023, Номер 25(25), С. 4621 - 4626

Опубликована: Июнь 15, 2023

We present here an iridium-catalyzed diastereo- and enantioselective [4 + 1] cycloaddition reaction of hydroxyallyl anilines with sulfoxonium ylides under mild conditions, leading to 3-vinyl indolines in moderate good yields excellent enantioselectivities. Control experiments disclosed a plausible mechanism.

Язык: Английский

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Enantioselective synthesis of spiro-N,O-ketals via iridium and Brønsted acid co-catalyzed asymmetric formal [4+2] cycloaddition

Chemical Communications, Год журнала: 2024, Номер 60(11), С. 1448 - 1451

Опубликована: Янв. 1, 2024

An asymmetric formal [4+2] cycloaddition of cyclic enamides with 2-(1-hydroxyallyl)phenol via iridium and Brønsted acid co-catalysis has been achieved to afford chiral N -unsubstituted spiro- , O -ketals.

Язык: Английский

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Iridium/Acid Dual-Catalyzed Enantioselective Aza-ene-type Allylic Alkylation of Nitro Ketene Aminals with Racemic Allylic Alcohols

Organic Letters, Год журнала: 2024, Номер 26(2), С. 508 - 513

Опубликована: Янв. 5, 2024

The enantioselective allylic alkylation of nitro ketene aminals with racemic alcohols was realized by iridium/acid dual catalysis. An allyl group installed on the α-position in a branched-selective manner high efficiency excellent enantioselectivities (93–99% ee). protocol applied to late-stage modification neonicotinoid insecticides, which directly furnished novel analogue good insecticidal activity against Aphis craccivora (LC50 = 6.40 mg/L). On basis control experiment, an aza-ene-type reaction mechanism proposed.

Язык: Английский

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Iridium-Catalyzed Highly Enantioselective and Chemodivergent Coupling Reaction of Vinyl Azides and Vinyl Benzoxazinones

Organic Chemistry Frontiers, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 15, 2024

An iridium-catalyzed enantioselective coupling reaction of vinyl azides and benzoxazinones provided access to a new class enantioenriched N-heterocycles, 3,4-dihydroquinolin-2(1 H )-imines.

Язык: Английский

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Enantioselective Ir-Catalyzed Allyl Alkylation/Semipinacol Rearrangement

Organic Letters, Год журнала: 2024, Номер 26(6), С. 1224 - 1228

Опубликована: Фев. 2, 2024

The semipinacol rearrangement is a powerful and versatile method for constructing all-carbon quaternary stereocenters. development of catalytic asymmetric rearrangements using multifunctionalizable electrophiles remains highly sought-after in organic synthesis. In this study, enantioselective allylic cation-induced reaction was presented that enables the simultaneous construction two skipped chiral carbon centers. Chiral Ir(I)-(P,olefin) Sc(OTf)3 catalysts cooperatively initiate alkylation alkenyl cyclobutanols with alcohols, triggering ring expansion cyclobutanol moiety through stereoselective 1,2-alkyl migration. afforded range cyclopentanones bearing an α-quaternary adjacent to allyl scaffold. products were applied synthesize enantioenriched fused tricyclopentanoids four stereogenic

Язык: Английский

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Enantioselective synthesis of 2-amino-4H-chromene derivatives with antifungal activities on phytopathogenic fungi

Organic Chemistry Frontiers, Год журнала: 2024, Номер 11(13), С. 3692 - 3699

Опубликована: Янв. 1, 2024

An Ir-catalyzed enantioselective cascade allylation/cyclization reaction of 2-(1-hydroxyallyl)phenols was developed, affording antifungal 2-amino-4 H -chromene derivatives with good to excellent enantioselectivities.

Язык: Английский

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Brønsted acid catalyzed [4 + 2] cycloaddition for the synthesis of bisbenzannulated spiroketals with antifungal activities

Organic & Biomolecular Chemistry, Год журнала: 2024, Номер 22(23), С. 4656 - 4661

Опубликована: Янв. 1, 2024

The intermolecular [4 + 2] cycloaddition of

Язык: Английский

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Synthesis of Some New Chiral Triazole-oxazoline Derivatives

Current Organic Synthesis, Год журнала: 2024, Номер 22(1), С. 136 - 142

Опубликована: Июль 12, 2024

: Some new (S)-2-[1-aryl-5-methyl-1H-1,2,3-triazol-4-yl]-4-benzyl-4,5-dihydro-ox-azoline were synthesized by the reaction of (S)-N-(1-hydroxy-3-phenylpropan-2-yl)-1-aryl-5-methyl-1H-1,2,3-triazole-4-carboxamides which prepared from aromatic amine as start-ing materials, with p-toluenesulfonyl chloride, triethylamine and DMAP. The structures characterized 1H NMR, 13C MS IR. chiral triazole-oxazoline was used a ligand in Diels-Alder asymmetric catalytic between 3-allyl-1,3-ox-azolidin-2-ketone 2-methyl-1,3-butadiene, using PdCl2 catalyst. (S)-3-(4-methylcyclo-hexe-3-ene-1-formyl)-1,3-oxazolidin-2-one obtained. Background: ligands are rarely reported. Objective: aim study to synthsize some (S)-4-benzyl-2-(1-aryl-5-methyl-1H-1,2,3-triazole-4-yl)-4,5-dihydrooxazoline (5a-g). Methods: one-pot methods oriented synthesis adopted. This provides sim-ple effective method for derivatives. Results: (5a-g) cyclization 3-allyl-1,3-oxazolidin-2-ketone 2-methyl-1,3-butadiene catalyzed (S)-4-triazole-oxazoline ligands. Conclusion: (S)-4-benzyl-2-(1-aryl-5-methyl-1H-1,2,3-triazole-4-yl)-4,5-dihydro-oxazoline corresponding N-[(S)-1-hydroxy-3-phenylpropan-2-yl]-1-aryl-5-methyl-1H-1,2,3-triazole-4-formamide, through method. After preliminary evaluation, triazoline-oxazoline ligands, 1,2,3-triazole rings, like pyridine-type materials saved replace one oxazoline ring di-oxazoline reactions.

Язык: Английский

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Six-membered ring systems: With O and/or S atoms

Progress in heterocyclic chemistry, Год журнала: 2024, Номер unknown, С. 421 - 484

Опубликована: Янв. 1, 2024

Язык: Английский

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