Direct Substitution of 2‐Aminotropones with Potassium Allyltrifluoroborates through Transition‐Metal‐Free C–N Bond Cleavage DOI
Qianqian Wu, Yan Wang, Muliang Zhang

et al.

Asian Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 13(11)

Published: Aug. 28, 2024

Abstract The poor nucleofugality of the amino group renders C−N bond functionalization primary aromatic amines highly challenging. Herein, we report a direct substitution reaction 2‐aminotropones, bearing unique non‐benzenoid seven‐membered ring that exists in some natural products and bioactive molecules, with potassium allyltrifluoroborates through cleavage under transition‐metal‐free conditions. 2‐aminotropones were directly substituted presence sodium bicarbonate, delivering structurally diverse 2‐allyltropones moderate to good yields. is free directing groups, activating groups transition metals, providing convenient method access tropones.

Language: Английский

Late-stage benzenoid-to-troponoid skeletal modification of the cephalotanes exemplified by the total synthesis of harringtonolide DOI Creative Commons
Stefan Wiesler, Goh Sennari, Mihai V. Popescu

et al.

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

Published: May 15, 2024

Abstract Skeletal modifications enable elegant and rapid access to various derivatives of a compound that would otherwise be difficult prepare. They are therefore powerful tool, especially in the synthesis natural products or drug discovery, explore different improve properties candidate starting from common intermediate. Inspired by biosynthesis cephalotane products, we report here single-atom insertion into framework benzenoid subfamily, providing troponoid congeners — representing reverse proposed (i.e., contra-biosynthesis approach). Computational evaluation our designed transformation prompted us investigate Büchner–Curtius–Schlotterbeck reaction p -quinol methylether, which ultimately results harringtonolide two steps cephanolide A, had previously prepared. Additional computational studies reveal unconventional selectivity outcomes driven choice Lewis acid nucleophile, should inform further developments these types reactions.

Language: Английский

Citations

9
Electrochemical Nickel-Catalyzed C(sp2)-H Functionalization of Tropones with Aldehydes DOI Creative Commons
Andrea Brunetti, Sofia Kiriakidi,

Mauro Garbini

et al.

ACS Catalysis, Journal Year: 2025, Volume and Issue: unknown, P. 3184 - 3190

Published: Feb. 6, 2025

A direct electroreductive functionalization of tropones employing aldehydes as alkylating agents is reported. This C(sp2)-H process leverages the mediation electroactive nickel complexes, enabling a wide range both native and substituted (44 examples) to be alkylated selectively at α-position in high yields (up 90%). Combined electrochemical, spectroelectrochemical, computational analyses disclosed whole mechanistic pathway revealed key role played by reduced Ni complexes activating tropone core toward condensation with aldehydes.

Language: Английский

Citations

1
Total Synthesis of Cephanolide A and Harringtonolide: A Unified Strategy Connecting Benzenoid and Troponoid Cephalotaxus Diterpenoids DOI Creative Commons

Zi-An Zhang,

Xu-cheng Gan,

Guang Tian

et al.

Published: Feb. 14, 2024

The fascinating benzenoid and troponoid Cephalotaxus diterpenoids are highly related biosynthetically, both of which popular targets for total synthesis. Herein, we describe a unified strategy the concise synthesis cephanolide A harringtonolide in 14 16 steps respectively. Palladium catalyzed Csp2-Csp3 cross-coupling followed by doubly electron-deficient intramolecular Diels-Alder reaction secure rapid construction carbon framework. Late-stage benzenoid-to-troponoid ring expansion was accomplished employing Büchner-Curtius-Schlotterbeck (BCS) reaction, furnishing two from A. This work shed light on chemical synthetic connection between diterpenoids.

Language: Английский

Citations

7
Late-Stage “Benzenoid-to-Troponoid” Skeletal Modification of the Cephalotanes: Total Synthesis of Harringtonolide and Computational Analysis DOI Creative Commons
Stefan Wiesler, Goh Sennari, Mihai V. Popescu

et al.

Published: Feb. 6, 2024

Inspired by the biosynthesis of cephalotane natural products, we envisioned that a “single-atom insertion” into framework benzenoid subfamily would provide access to troponoid congeners — representing reverse proposed (i.e., “contra-biosynthesis” approach). Computational evaluation our designed transformation prompted us investigate Büchner–Curtius–Schlotterbeck reaction p-quinol methylether, which ultimately resulted in synthesis harringtonolide two steps from cephanolide A, had previously prepared. Additional computational studies revealed unconventional selectivity outcomes were driven choice Lewis acid and nucleophile, should inform further developments these types reactions.

Language: Английский

Citations

5
Photochemical synthesis in inorganic chemistry DOI

Rimsha Kanwal,

Riyadh R. Al-Araji,

Ahmad H. Ibrahim

et al.

Reviews in Inorganic Chemistry, Journal Year: 2024, Volume and Issue: 44(3), P. 323 - 337

Published: Feb. 16, 2024

Abstract In the last few decades, photochemistry has great influence on all type of synthetic processes. While photochemical synthesis is emerging field in inorganic chemistry as it impart various magnificent properties to materials that are used for nano-sized giant supramolecular structures. There many based approaches like electron, atom, energy transfer depending upon need product where one can switch pathway. A variety compounds have been synthesized dienes, nitrides, indoles, gold nano-particles and structures using route. Photochemical applications artificial photosynthesis fluorophores.

Language: Английский

Citations

4
Electrochemical Site‐Selective Alkylation of Tropones via Formal C(sp3)−C(sp2) Coupling Reaction DOI Creative Commons
Andrea Brunetti,

Mauro Garbini,

Nico G. Kub

et al.

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(9), P. 1965 - 1971

Published: March 5, 2024

Abstract The first site‐selective electrochemical alkylation of tropones is realized by reacting 2‐acetoxytropones and redox‐active‐esters (RAEs). electroreductive protocol enables the preparation mono‐ disubstituted in high yields (up to 71%) under very mild conditions. Dedicated voltammetric measurements served for identification as a class valuable trapping agents nucleophilic radical species shed light on whole mechanistic profile. Wide tolerance towards functional groups (27 examples) application late‐stage functionalization bioactive compound ( i. e . Colchicine analogue), emphasize synthetic impact present methodology.

Language: Английский

Citations

4
Visible-light-mediated site-selective C(sp2)–H alkylation of tropones facilitates semi-synthesis of cephafortunoids A and B DOI Creative Commons
Q. Zeng, Cheng‐Yu Zheng,

Zhan‐Peng Ge

et al.

Chemical Science, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

An efficient visible-light-driven method for achieving α-site-selective C–H alkylation of tropones was developed. It applied to transform fortunolide A into cephafortunoids and B, marking the first synthesis C 20 Cephalotaxus troponoids.

Language: Английский

Citations

0
-Derivatization of Natural Tropolone and β-Thujaplicin Leading to effective Inhibitors of Human Carbonic Anhydrases IX and XII DOI Creative Commons
Francesco Melfi, Ilaria D’Agostino, Simone Carradori

et al.

European Journal of Medicinal Chemistry, Journal Year: 2025, Volume and Issue: unknown, P. 117552 - 117552

Published: March 1, 2025

Language: Английский

Citations

0
Studies Concerned with the Structure and Synthesis of the Anti‐viral Tropolone Glycoside Liriosmaside A DOI Creative Commons
Qi Chen,

Yaping Zhan,

Michael G. Gardiner

et al.

ChemistryOpen, Journal Year: 2025, Volume and Issue: unknown

Published: April 8, 2025

Abstract A bromotropone corresponding to the agylcone of glycosylated sesquiterpenoid natural product liriosmaside has been prepared over ten steps and in a fully regio‐controlled manner through gem ‐dibromocyclopropane‐mediated ring‐expansion readily accessible decalenone. Pd[0]‐mediated glucosylation reaction applied this afforded mixture from which an enantiomerically pure cross‐coupling could be obtained its structure confirmed single‐crystal X‐ray analysis derivative. Various (unsuccessful) attempts are described selectively acylate last compound thereby install 3‐hydroxy‐3‐methylglutaric acid or HMGA‐containing side chain title product. literature survey other products embodying HMGA motif suggest that co‐metabolite B S ‐configured at C3”. The evaluation glucosylated tropone series anti‐bacterial, anti‐fungal cytotoxicity assays reveals it is inactive all these so emphasizing prospect related troponoids, including B, can serve as useful models for new anti‐viral agents.

Language: Английский

Citations

0
Diastereoselective (8+3)‐Cycloadditions of Donor‐Acceptor Cyclopropanes with Tropothione DOI
Grzegorz Mlostoń, Mateusz Kowalczyk, Marcin Palusiak

et al.

European Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 27(6)

Published: Dec. 27, 2023

Abstract Reactions of dimethyl 2‐arylcyclopropane‐1,1‐dicarboxylates, used as representatives D‐A cyclopropanes, with tropothione were carried out in the presence scandium triflate a catalyst, under mild conditions (CH 2 Cl solution, rt). The anticipated (8+3)‐cycloaddition products, cycloheptatriene fused thiopyrans, obtained good to excellent yields. Cycloadditions occurred complete diastereoselectivity and all cases single diastereomers formed. Structures isolated cycloadducts established based on spectroscopic data two they unambiguously confirmed by crystal X‐ray diffraction analysis. In contrast an analogous reported for parent tropone, which was performed Ni(ClO 4 ) , no 1,3‐ H shift leading products possessing CH moiety located within seven‐membered ring observed.

Language: Английский

Citations

9