Backbone-Enabled and Ester Groups Switched δ-C(sp²)–H Amination/Fluorination: Cyclic Dipeptides Synthesis

Organic Letters, Год журнала: 2024, Номер 26(24), С. 5130 - 5135

Опубликована: Июнь 6, 2024

An efficient and concise strategy for the synthesis of cyclic dipeptides via Pd-catalyzed site-selective δ-C(sp2)–H amination/fluorination N-to-C cyclization is disclosed. The backbone amides within serves as endogenous directing groups, while desired products were switched by C-terminal ester group. This chemistry presents a novel robust alternative to construct cyclodipeptide fragments.

Язык: Английский

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Organoboron catalysis for direct amide/peptide bond formation

Chemical Communications, Год журнала: 2024, Номер 60(80), С. 11202 - 11222

Опубликована: Янв. 1, 2024

This review explores studies on the development of direct dehydrative amide/peptide bond formation from carboxylic acids using organoboron catalysis.

Язык: Английский

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Synthesis of N-methyl secondary amides via diboronic acid anhydride-catalyzed dehydrative condensation of carboxylic acids with aqueous methylamine

Organic & Biomolecular Chemistry, Год журнала: 2025, Номер 23(10), С. 2400 - 2410

Опубликована: Янв. 1, 2025

In this study, we present the first catalytic methodology for synthesizing N-methyl secondary amides via dehydrative condensation of hydroxycarboxylic acids with readily available and safe aqueous methylamine, employing diboronic acid anhydride (DBAA) as catalyst. DBAA catalysis can also be applied to direct amidations using ethylamine or dimethylamine. Moreover, demonstrate applicability system concise synthesis eight biologically active compounds containing β-amino alcohol motifs, including halostachine, synephrine, longimammine, phenylephrine, metanephrine, normacromerine, etilefrine, macromerine.

Язык: Английский

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Enantioselective Access to Chiral 2,5-Diketopiperazines via Stereogenic-at-Cobalt(III)-Catalyzed Ugi-4CRs/Cyclization Sequences

The Journal of Organic Chemistry, Год журнала: 2023, Номер 88(22), С. 16024 - 16037

Опубликована: Ноя. 2, 2023

An asymmetric synthesis of chiral 2,5-diketopiperazines by the Ugi-4CR/cyclization is exhibited. The employment catalytic anionic Co(III) complexes delivered α-propiolyl aminoamides in high yields with excellent enantioselectivities (31 examples, up to 95% ee). following treatment Ugi-adducts PPh3 leads 2,5-DKPs without significant loss (26 91%

Язык: Английский

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Synthesis of Monodehydro-Diketopiperazines Enabled by Cp*Rh(III)-Catalyzed Amine-Directed N–H Functionalization

Organic Letters, Год журнала: 2024, Номер unknown

Опубликована: Сен. 27, 2024

A two-step, diversity-building sequence to prepare monodehydro-diketopiperazines from readily accessible materials is reported. Rh(III)-catalyzed, amine-directed N-H functionalization of a variety α-amino amides with diazophosphonate ester and subsequent cyclization gives phosphonate-substituted diketopiperazines. Horner-Wadsworth-Emmons reaction then provides high

Язык: Английский

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Diastereoselective Spirocyclization: Entry to Spirocyclic Diketopiperazines

Organic Letters, Год журнала: 2023, Номер 25(43), С. 7822 - 7826

Опубликована: Окт. 19, 2023

We report a novel approach to access spirocyclic compounds containing diketopiperazine (DKP) motif fused on pyrrolidine ring. The shared carbon is at the ketone oxidation state, bearing two carbon-nitrogen bonds, one of which introduced stereoselectively during cyclization event. reaction proceeds through an acid-catalyzed pendent chiral aminoamide unit onto 2,3-dehydroproline amide moiety with up >98:2 diastereoselectivity. have demonstrated generality this methodology and its applicability chemically diverse DKP-containing structures. extent stereoinduction how it varies according bulkiness substituent substrate set. This gives underexplored that may be useful in identifying new bioactive molecules.

Язык: Английский

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Diboronic Acid Anhydride-Catalyzed Synthesis of Serine or Threonine Containing 2,5-Diketopiperazines

Synfacts, Год журнала: 2023, Номер 19(08), С. 0844 - 0844

Опубликована: Июль 14, 2023

Key words diboronic acid anhydride catalysis - 2,5-diketopiperazines serine threonine

Язык: Английский

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